US2037155A - Control structure - Google Patents

Description

April 14, 1936.

w. w. STUART 2,03 7,155

CONTROL STRUCTURE Filed Aug. 7, 1933 Patented Apr. 14, use

UNITED STATES PATENT CWFICE (ION'IPROL STRUCTURE William W. Stuart, Des Moinea. Iowa Application August 7, 1933, Serial No. 684.002

4 Claims. (Cl. 200-140) The object of my invention is to provide a control structure of very simple, durable and inexpensive construction, whereby a switch or other control element is actuated for moving a control member in one direction when one sensitive element is affected by rising temperature while the other is affected by falling temperature, and for moving the control member in the other direction when one sensitive member is 0 aflected by falling temperature and the other is ail'ected by rising temperature, or to provide a control operated from two temperature sensitive elements subject to temperatures in diiierent locations and serving to actuate the control from one position to the other when the temperatures affecting the sensitive elements reach a predetermined relation.

In such a control, there is no change in the operative position of the control member when the sensitive members are actuated in the same direction to the same extent.

with this and other objects in view, my invention consists in the construction, arrangement and combination of the various parts oi my control structure, whereby the objects contemplated are attained, as hereinafter more fully forth, pointed out in my claims, and illustrated in the accompanying drawing, in which:

Figure l is a sectional view illustrating my con trol member as applied to a refrigerating system in a building.

Figure 2 is a perspective view showing the control with the operative parts enclosed in a suitable casing.

Figure 3 is another sectional view illustrating another application of the control.

Figure 4 is a diagrammatic showing of a slight- 1y modified form of my invention; and

Figure 5 is a diagrammatic showing of another form in which the invention may be embodied.

Construction shown in Figure 1 I have shown in Figures 1 and 3, two practical applications of my control. In Figure 1, I have shown a cooling apparatus in a house adapted to be-actuated for cooling the house when the difierence between the outside and inside temperatures goes below a certain predetermined relation, and in which the cooling apparatus becomes imperative when that given relation 01' temperatures outside and inside is reached.

In the accompanying drawing, I have used the reference numeral II to indicate a suitable casing for holding certain working parts of my control and ail'ording a support thereto: and tar affording a suitable means on which the control may be assembled and by which it may be stored, transportedand mounted where desired.

The case I0 has a removable side plate II, which may be fastened in position by a screw 5 bolt l4. In the case In, there is arranged a movable control member i6 and a pair of temperature sensitive elements It. The particular kind of sensitive element and the arrangement thereof are simply illustrative of my invention and 10 other kinds and arrangements might be employed.

In the illustration here used, I use for the movable control member, a mercury switch, which has at one end the contact point 20 and 22 con- 15 nected with conducting wires 24 and 26 leading to binding posts 21 and 28 mounted in the wall of the casing and connected in turn with the conducting wires III and 32. The'sensitive elements here illustrated are the known metal bel- 2o lows. Extending upwardly from the heads of the respective bellows are ears or the like 34 and 36. These are connected by a rock bar or cross bar 38, having the upward central extension 40, on which the control member I is mounted as 25 by means of a strap 42.

Connected with the respective bellows are tubes 44 and 46, which have at their ends the ordinary bulbs 48 and 50. It will be understood, of course, that the bulbs, tubes and bellows con- 30 tain material expansible and contractable according to temperature.

The bulb 48 is located within the room 52 and the bulb 50 is located where it is subject to outside. temperature, 5

One oi the bellows. is provided with adjusting mechanism 54 of any suitable kind andfwith an indicating finger 5i projecting through a slot 58 in the -wall of the casing. The wall of the casing adjacent the slot is provided with gradua 4o tions 60.

I provide for instancein the base 62 below the room 52 a mechanical refrigerator oi known construction;- for instance of the type having an expansion coils; a condenser 65- and a pump 45 it operated by a motor 68. The expansion or cooling coil 64 is arranged in a passage 10.

Ari inlet passage 1! permits air to flow from the room 52 to the passage 10, and an outlet passage I4 permits air to flow from the passage 50 It in the room. The air may thus be circulated past the cooling coil 64.

In the passage ll is a fan it operated by a motor 70.

Sue current supply wire leads to the binding post 28. The other current supply wire 88 leads to the motor 68 and has a branch 82 leading to the motor '13. The wire 38 leads from the motor 18 to a binding post 21 and has a branch 84 leading to the motor 68.

Operation of apparatus shown in Figure 1 I shall now describe the practical operation of my control structure when arranged in the environment illustrated in Figure 1.

Let us assume that it is the desire to operate the cooling mechanism whenever the temperature in the room is less than below the temperature outside and to stop the cooling mechanism whenever the temperature in the room is 10 or more colder than the outside temperature.

The left-hand bellows I8 is adjusted by means of the mechanism 54 to bring the finger 56 to the proper position as illustrated for instance in Figure 2, so as to get the desired result mentioned. It will, of course, be understood that the parts may be adjusted and set for accomplishing this purpose. That is to say, the left-hand bellows is adjusted so that when the inside temperature rises to the point where it is less than 10 below the outside temperature, the cooling apparatus will be started.

It will be observed that when both inside and outside temperatures rise in the same proportion, the cross bar 38 and the control member I6 will be raised, but the control member I6 will not be moved to afiect any operation. Similarly when the bellows contract equally, there will be no such eifect on the control member I6 as to cause it to change from one operative position to the other.

However, if the temperature affecting the bulb 48 goes up or the temperature affecting the bulb 58 goes down until the temperature affecting the bulb 48 is less than 10 below the temperature affecting the bulb 58, the bar 38 and the member I6 will be tilted to bring the mercury in the bulb to position for closing the contacts 22 and 28 and thus closing the circuit, whereupon the motor 68 will be energized for operating the pump 66 and operating the cooling mechanism.

It will be understood that the bellows are so adjusted that such increasing of the temperature affecting the bulb 48 with relation to the temperature affecting the bulb 58 causes expansion of the left-hand bellows I8 and thus tends to rock the bar 38 and the member I6 to the contact closing position illustrated in Figure 1. Similarly, a lowering in the temperature affecting the bulb 58 with relation to the temperature affecting the bulb 48 causes contraction of the right-hand bellows I8 and produces the same result.

It may be mentioned at this time that when the device is inoperative, a lowering of the temperature affecting the bulb 48 simply effects a further contraction of the left-hand bulb I8 and has no effect upon the operation of the device. Likewisewhen the temperature in the room is 10 below the temperature outside, an increase in the outside temperature eflects an expansion of the right-hand bellows I8, but does not effect any operation of the member I6.

The motor I8 is so connected that it will be energized at the same time as the motor 68 for operating the fan and thus causing circulation through the passage 18 past the cooling coil 64 and into the room 52.

When the temperature in the room 52 drops to the point where it is 10 below the temperature outside, the lefthand bellows I8 will have cantracted relatively for causing rocking movement of the bar 38 and the member I6 and for causing the mercury to leave the contacts 2228 for thus breaking the circuit. Should the temperature in the room continue to drop until it is more than 10 below the outside temperature, the control is not afiected.

I am thus able to operate the cooling system so as to maintain the temperature in the room at a given point below the temperature outside.

The apparatus may be provided with limiting devices so that the room may not be kept at the predetermined relation to outside temperature where that is undesirable.

Construction shown in Figure 3 In Figure 3, I have shown another practical application of my control.

In this figure, I have illustrated a mechanism operated from the control, whereby when the outside air is colder than the air in a house, it will be drawn into and circulated through the. house, and when the outside air is no colder or is warmer than the air inside, the house, no outside air is drawn into the house. but a circulation of the air in the house is maintained.

I utilize the ordinary unused furnace and the pipes connected therewith for the circulation of the air. The installation shown in this figure is, of course, intended primarily for summer use.

The control shown in Figure 3 is the same as that shown in Figure 1, except that the control member I6 has contacts 22a and 28a at the opposite end of the bulb from the contacts 22-28, so that the tilting of the bulb in either direction closes a circuit for purposes as hereinafter set forth.

In Figure 3, I have shown a building having the rooms 86 and 88 and the basement 89 and the attic 98.

The building is equipped with a heating system including a furnace 9I from which the heat pipes 92 lead to the rooms 86 and 88. An air conducting passage 94 leads to the lower part of the furnace. The passage 94 has an air inlet 96 for permitting intake of outside air and has intake passages 98 and I88 from the rooms 86 and 88.

For controlling the flow of air from the outside through the inlet 96, I provide a damper I82 normally tensioned to closed position by means of the spring I84 and connected with a movable core of a solenoid I86.

In the passage 94 between the inlet 96 and the closest of the inlets 98 and I88, I place a damper I88 normally tensioned to closed position by a spring H8 and connected with the movable core of a solenoid H2.

The current supply wire H4 is connected with the contacts 22 and 22a and is connected by a branch wire II6 with a motor II8 for operating a fan I28 in the passage 94 between the inlet 96 and the furnace 9 I.

In the ceilings of the rooms 86 and 88 are openings I22 and I24 controlled by suitable louvre dampers I26 and I 28, which are yieldingly ten sioned toward closed position by means of the springs I38 and I32 and are operatively connected with the movable cores of the solenoids I34 and In the wall of the attic 98 is an outlet opening I38. Adjacent this opening is a fan I48 for blowing air out of the attic. The fan I48 is operated by a motor I42,

I shall now refer to the various circuits 'for controlling the mechanisms above described.

From the motor II8 leads a wire I44, which connects with a wire I45. The wire I45 is in turn connected with a wire I46, which is the other current supply wire.

Whenever the system is operating by the closing of the main switch not here shown, the motor H8 and the fan I20 will be in operation.

When the outside temperature aifecting the bulb 50 is below the inside temperature affecting the bulb 48, the right-hand bellows I8 will be contracted for tilting the bar 38 and the control member I6 to position where the mercury closes the circuit between the contacts 22 and 20. The current conducting wire II4 has a branch I48 which is connected to the contact 22.

The contact 20 is connected by a wire I50 with the motor I42. The motor I42 is connected with a wire I52, which is in turn connected with the wire I46.

Operation of apparatus shown in Figure 3 Thus when the circuit is closed through the contacts 22 and 20, it is likewise closed through the motor I42 for causing operation of the fan I40 and driving the air out of the attic.

At the same time, the damper I08 is closed by the spring H and there is no circuit through the solenoid II2.

At the same time also, the louvres I26 and I28 are held open by their solenoids, which are included in circuit as follows:

A branch wire I54 leads from the wire I45 and a wire I56 leads from the wire I54 to the solenoid I06. In turn, the wire I58 leads from the solenoid I06 to the wire I50. Thereby when the circuit is closed through the points 22 and 20, the solenoid I06 is energized for opening the damper I02 for drawing in outside air (the cooler air).

Leading from the line I50 to the solenoid I34 is a wire I60 and a wire I62 leads in turn from the solenoid I34 to the wire I46, so that when the circuit is closed through the contacts 22 and 20, the solenoid I34 is energized for opening the louvres I26.

A wire I64 leads from the wire I50 to the solenoid I36 and a wire I66 leads from the solenoid I36 to the wire I46 for thus at the same time closing the circuit through the solenoid I36 and opening the louvres I28. Thus it will be seen that when the outside temperature is below the inside temperature, the circulation of outside air through the rooms is established.

If on the other hand, the outside temperature rises or the inside temperature goes down, until they are substantially the same, the arm 38 and the member I6 rock to position where the mercury leaves the contact points 22 and 20 and closes the circuit between the contacts 20a and 22a.

It will, of course, be understood that there is a slight differential which I have not mentioned in describing this operation. In actual practice, the apparatus is usually set to operate only at such temperature relations, as justify putting of the apparatus to work.

When the movement of the member I6 last referred to occurs, the circuit is broken through the solenoid I06 and the solenoids I32 and I36 and through the motor I42, and the springs close the damper I02 and the louvres I26 and I28.

The contact points 2011' and 22a are in circuit with the solenoid I I2 in the following manner:

A wire I68 leads from the wire 4 to the contact point 22a. The wire I leads from the contact 20a to the solenoid II2.

A wire I12 leads from the solenoid II2 to the wire I54 and thence to the wire I46. Thus when the circuit is closed through the points 20a and 22a, it is likewise closed through the solenoid II2 for opening the damper I08 for causing a circulation of the air in the rooms 86 and 88. By removing the air duct between the damper I02 and the motor III, the whole basement may be utilized as a plenum chamber.

Many other applications of my control may be made. It is adapted for use wherever it is desired to actuate a control from one position to another when the temperatures affecting the sensitive elements reach a predetermined relation, which re lation may be varied considerably as may be seen from the foregoing illustrations.

It will, of course, be understood that modifications may be made in many respects in the elements used and in the construction and arrangement of parts of my control without departing from the essence of my invention. For instance, both of the temperature sensitive bellows devices or whatever may be used as substitutes therefor may be made adjustable.

It is obvious that my control may be used with a great many different kinds of other limiting devices or controls. For instance in the application shown in Figure 3,whileltmaybe desirable to draw cooler outside air under ordinary circumstances, it may likewise be important under certain circumstances to put on a limit control, which will shut down the equipment independently of my control, when the temperature in the house reaches some predetermined low limit, as for example 60.

Other instances might be given, but these will illustrate the great variety of possible uses to which a control of this kind may be put and of situations in which it may be used. Likewise any compensating adjustments desired may be provided in the control mechanism.

Again it is readily possible to arrange the mechanism between the sensitive elements and the control member I6 in such manner that the control member is not bodily moved but is tilted at the proper times in the relative movements of the sensitive elements, as illustrated diagrammatically in Figure 4.

So also the control may be arranged to slide the control member, as illustrated diagrammatically in Figure 5.

The control member may be made to operate a valve or other mechanism instead of closing a switch.

The mechanism could be arranged to maintain room temperature above outside temperature if desired. The outside temperature affecting the outside sensitive element may be outdoor air or air in another room or place.

The control may be used for keeping other fluids as well as air surrounding chemicals, ceramics or other products or materials cooler or warmer than the objects cooled or warmed by the fluids.

The device shown in Figure 3 could be used omitting the fan I40, or where there is no desire to recirculate the air in the room, the fan I20 may be omitted.

I claim as my invention:

1. In a control, a casing having an opening in its wall, an expansible bellows mounted in the casing for adjustment to a variety of positions, means outside the casing for effecting such adjustment, means associated with such bellows and projecting through the opening for indicating the condition of adjustment of the bellows, a second expansible bellows in the casing, temperature sensitive elements located in diflerent places and operatively connected withthe respective bellows, a switch, and means interposed between the switch and the two bellows for operating the switch in accordance with the relative movement of the bellows.

2. In a control, a casing having an opening in its wall, an expansible bellows mounted in the casing for adjustment to a variety of positions, ex-

pansible and contractible according to temperature at a given location, means outside the casing for efiectiug such adjustment, means associated with such bellows and projecting through the opening for indicating the condition of adjustment or thebellows, a second expansible bellows in the casing, expansible and contractible according to temperature at another location, a switch, and

, means interposed between the switch and the two bellows for operating the switch in accordance with the relative movement of the bellows.

3. In a control, a casing, having an opening in its wall, a temperature sensitive device mounted in the casing for bodily adjustment to a variety of positions subject to the temperature at a given location and inherently movable in accordance with variations in temperature, means (or eifecting such adjustment, means associated with such device and visible by reason of the opening for indicating the condition of adjustment of the device, a second temperature sensitive device in the casing subject to the temperature at another given location and inherently movable in accordance with variations in temperature, a switch, and means interposed between the switch and the two devices for operating the switch in accordance with the relative movements of the two devices induced by temperature changes.

4. In a control, a casing having an opening in its wall, an expansible bellows mounted in the casing for adjustment to a variety of positions, means forv effecting such adjustment, means associated with such bellows and visible by reason of the opening for indicating the condition of adjustment of the bellows, a second expansible beilows in the casing. temperature sensitive elements located in different places and operatively connected with the respective bellows, a switch, and means interposed between the switch and the two bellows for operating the switch in accordance with the relative movement of the bellows.

WILLIAM W. STUART.

Images