US1749392A - Temperature control switch structure - Google Patents

Description

March 4, 1930. PENN 1,749,392

TEMPERATURE CONTROL SWITCH STRUCTURE Filed March 10, 1928 2 Sheets-Sheet 1 March 4, 1930. A. PENN 1,749,392

TEMPERATURE CONTROL SWITCH STRUCTURE Filed March 10, 1928 2 Sheets-Sheet 2 Patented Mar. 4, 1930 UNITED STATES PATENT OFFICE ALBERT PENN, OF DES -MOINES, IOWA, ASSIG-NOR TO PENN ELECTRIC SWITCH 00., OF

I DES MOINES, IOWA, A CORPORATION OF IOWA TEMPERATURE CONTROL SWITCH STRUCTURE Application filed March 10, 1928. Serial No. 260,796.

The object of my invention is to provide a temperature control switch structure of simple, durable, and comparatively inexpensive construction.

A further object is to provide a structure of this character in which a switch is controlled by a temperature actuated bellows element so that an electric circuit may be es tablished or broken, depending on the tem- 19 perature of the atmosphere surrounding the bellows element.

Another object is to provide such a device with a means for supporting the bellows element and a spring mounted in opposition to the element whereby both the force of the spring and the element act upon the switch.

Still a further object is to provide a lever for adjusting the tension of the spring so that the switch will be actuated for making or breaking an electric circuit and the range of operation of the structure can be varied by movement of this lever to any desired position.

Still a further object is to provide a base with a yoke on it for pivotally supporting a switch arm and for supporting the bellows element in position to coact with the switch arm, the lever being mounted against the base and the spring associated therewith and mounted to oppose the bellows element.

Heretofore it has been customary, in devices of this character where the furnace controlling mechanism is remotely controlled by a room thermostat, to provide a pilot or relay circuit wherein the room thermostat controls a small current which current in turn actuated a relay switch for controlling the heavier current required for operating the motor connected with the furnace dampers or the blower motor in an oil burner installation. In order to entirely eliminate the relay circuit it has been my object to provide a switch adapted to easily control the heavier current even when placed at a distance from the motor.

To accomplish this result I provide a switch in which the circuit is quickly broken for reducing the arcing at the contacts and by providing main contacts for carrying most of the current when the switch is closed and auxiliary contacts for temporarily carrying the current for an instant as the circuit is made or broken, the auxiliary contacts being located in a magnetic field, the arcing is still further reduced and almost entirely eliminated.

It has therefore been a further object to provide a means associated with the switch arm for causing this quick action of the arm when the electric circuit is being made or broken whereby the entire controlling circuit may be carried by my device without the use of a pilot circuit.

With these and other objects in view my invention consists in the construction, arrangement and COHlbllliltiOIiOf the various parts of my device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims and illustrated in the accompanying drawings. Although the invention is susceptible of a variety of embodiments, it is unnecessary to fully describe and illustrate more than one in order to give a full understanding of the invention both from its structural and functional standpoints. Accordingly, I have illustrated a preferred and desirable embodi-- ment of the invention in the accompanying drawings in which:

Figure 1 is a front elevation of my device showing its appearance when installed on a wall in a living room or the like whereby it may be operated according to the temperature in the room.

Figure 2 shows a side elevation of my device.

Figure 3 is an enlarged sectional View on the line 3-3 of Figure 1..

Figure 4 shows a portion of Figure 3 with the parts thereof in a different position.

Figure 5 is a view similar to Figure 4,

showing the parts in still another position.

and illustrating in connection with the device an electric circuit controlled by the switch.

Figure 6 is a sectional view on the line 66 of Figure 3 illustratin the supporting yoke for the bellows and spring and the relation of these parts to each other.

Figure 7 is a sectional view on the line 7-7 of Figure 4 illustrating a portion of the switch structure; and

Figure 8 is a sectional view on the line 88 of Figure 6 showing the operating lever for varying the differential of operation of the temperature actuated bellows.

On the accompanying drawings I have used the reference numeral 10 to indicate a base. The base 10 supports the various parts of my structure and is designed to be attached to a wall by screws or other means. The base 10 has secured to its back side a conduit box 12 which may be concealed in a depression in the wall to which the base is secured for the purpose of housing electrical connections to the switch of my structure.

A yoke 14 is secured to the base 10 by means of screws 16 extending into feet 18 formed on the yoke. The yoke 14 is provided with a pair of projections 20.

v A yoke shaped switch arm 22 is pivoted in the yoke 14 by pins 24 extending rotatably into openings formed in the extensions 20. Secured to the arm 22 is an armature 26 adapted to support a main contact 28 and an auxiliary contact 30. The auxiliary contact 30 is mounted through an opening 32 formed in the armature 26 and is supported by a leaf spring 34 riveted to the armature 26 and the arm 22.

Secured to the base 10 is a block 36 of insulating material adapted to support a permanent magnet 38. The magnet 38 is held in position by a clip 40. The clip 40 supports a fixed auxiliary contact 42 adapted to coact with the contact 30. Secured to the block 36 is a fixed main contact 44 adapted to coact with the contact 28. The contacts 42 and 44 are connected together b a connector 46 as illustrated in Figure 3 o the drawings.

A flexible lead 48 is secured to a terminal 50 on the block 36 and has its free end secured to the armature 26 whereby the contacts 28 and 30 are electrically connected to a wire 52. A wire 54 extends from the terminal screw 57 and these two wires may be included in any electric circuit adapted to be controlled by the structure herein disclosed. By way of a 56 by means of the switch device thus far described, I provide a washer 62 having a notch 64 adapted to loosely receive a pin 66 extending from side to side of the yoke shaped arm 22 as best illustrated in Figure 6 of the drawmgs.

Secured tothe washer 62 is a bellows element 68 which is entirely sealed and provided with a head 70. The head 70 has secured thereto a supporting bolt 72 extending through the yoke 14. Adjusting nuts 74 are positioned on the bolt 72 on each side of the yoke 14 so that the position of the bellows element 68 can be initially adjusted at the factory for proper temperature operation. The washer 62 is provided with a flange 76.

Extending from the base 10 is a post 78, the end of which engages the washer 62 and acts as a limit stop for the washer in one direction. A second washer is slidably but non-rotatably mounted on the post 78 and a spring 82 is interposed between the washers 62 and 80. A shoulder is formed on the washer 80 for positioning the spring 82 thereon and the flange 76 serves the same purpose on the washer 62. It will be obvious that various positions of the washer 80 on the post 78 will cause different tensions of the spring 82 in opposition to the bellows element 68 so that the range of the operation of the bellows may be varied according to the wishes of the operator.

For adjusting the washer 80 relative to the post 78 I provide the following described mechanism.

A cam surface 84 is formed on the washer 80. A lever 86 best shown in Figure 8 of the drawings is pivoted on a shouldered bolt 88 extending into the base 10. The lever 86 is provided with an are shaped opening 90 so that the post 78 does not interfere with its swinging movement. A cam surface 92 is formed on the lever 86 adapted to coact with the camsurface 84 of the washer 80.

From the foregoing construction it will be obvious that swinging movement of the lever 86 will either impose additional tension on the spring 82 or reduce that tension depending on which way the lever 86 is swung. A pointer 94 is formed on the lever 86 which serves in conjunction with a scale 96 on the base 10 to indicate the degree of heat for which the device is set. a

In connection with my device I provide a cover member 102 for housing the switch structure and the bellows element. An extension 104 is provided for extending over the bellows element and the yoke 14. The cover member 102 is provided with flanges 106 extending over the sides of the base 10 and secured thereto by screws 108.

The cover member 102 and the extension 104 are provided with openings 110 for allowing the atmosphere temperature of the room to affect the bellows element readily.

A slot 112 is formed in the cover member through which the controlling lever 86 p l trudes so that it can be manipulated by an operator of the device.

If desired, a thermometer 114 can be mounted on the outside of the cover 102 for the purpose of indicating the temperature of the IOOIII.

Practical operation In the operation of my device, the lever 86 is set for the degree of heat desired to be maintained, for instance in a living room. Thereafter the switch operates automatically for either startin the motor 56 or stopping it depending on t e demands for an increase in temperature or for a reduction in temper ature. Assuming the switch to be in open position as illustrated in Figure 3, a reduction of the temperature affecting the bellows 68 will allow the armature 26 to move in the direction of the arrow 98 due to the tension of the spring 82. When the armature is close enough to the magnet 38 the attraction of the magnet will cause the contact to quickly contact with the contact 42 as shown in Figure 4 and the armature will be moved still farther causing the contact 28 to touch the contact 44 for establishing the electric circuit through both the main and auxiliary contacts as shown in Figure 5. When the temperature in the room increases above a predetermined point, the armature 26 will be moved in the direction of the arrow 10o first breaking the main contact as shown in Figure 4 and then the auxiliary contact. The

Y breaking of the auxiliary contact occurs in the iii) magnetic field so that any tendency tospark ing is immediately blown out by the action of the magnetic field.

The bellows 68 when the switch is opening accumulates a slight amount of energy in trying to overcome the magnetic field of the magnet 38. As soon as the armature 26 starts to move out of the strongest magnetic field, however, it immediately comes into a weaker field and at the same time the storedup energy operates on the switch arm for quickly breaking the contact which aflords and gives a snap action which is very desirable in a'switch of this kind. To further facilitate the action of the switch, the notch 64 is somewhat wider than the diameter of the pin 66, as shown in dotted lines in Figure 6, so that when the magnet 38 does'afi'ect the arm 26', the lost motion between the notch and the pin will allow slight move ment of the arm independent of the bellows 68 and spring 82.

Some changes may be made in the construction and arrangement of the various parts of my invention, without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims, any

modified forms of structure or use of mechan ical equivalents which may be reasonably in eluded within their scope.

I claim as my invention: 1. A structure of the character disclosed comprising a stationary contact, a yoke, a

movable armature pivoted thereto, a contact.

carried by said armature and adapted to enage the stationary contact when the armature 1s m one position of its movement, a magnet,

said armature being in close proximity to said magnet when in such position whereby a snap action switch is provided, a bellows having one end anchored to said yoke and its other end acting upon said armature for moving it in one direction and a spring opposing the action of said bellows.

2. A structure of the character disclosed comprising a stationary contact, a movable armature, a contact carried thereby and adapted to engage the stationary contact when the armature is in one position of its movement, a magnet, said armature being in close prox imity to said magnet when in such position whereby to cause quick action of the armature a spring associated with said armature for moving it to such position and a bellows opposing said spring and expandible upon an increase of temperature of the surrounding atmosphere, one end of saidspring being slidable longitudinally relative to the axis thereof whereby to vary the action of the bellows on the armature and means for locking such end of the spring in any of the positions to which it may be slid.

3. In a temperature controlled switch strncture, a base, a switch mounted thereon and including a fixed and a movable contact, an arm for supporting said movable contact, means associated with said arm for causing it to move quickly as the contact thereon is being separated from the fixed contact, a yoke mounted on said base, said arm being pivoted to said yoke, a temperature influenced bellows carried by said yoke and acting upon said arm for moving the same, a sprin counteracting the bellows, a post on said base and arranged on the axis line of said spring, a member longitudinally slidable relative to said post, a lever pivoted to said base at a point spaced from said post, and coacting cam surfaces on said lever and on said member. a

4. In a temperature controlled switch structure, abase, a switch arm pivotally mounted thereon, a temperature influenced bellowls carried and acting upon said arm for moving the same, a spring counteracting the bellows,

1 and means for adjusting the tension of said spring, said means comprising a member against one end of said spring, said member being slidable longitudinally relative to the axis of said spring but non-rotatable, a cam surface on said member; and a swingable adjusting lever having acam surface for coac- -tion with the cam surface of said member.

5. In a temperature controlled switch structure, a base, a switch mounted thereon and including a fixed and a movable contact, means for causing a quick separation of said contacts whereby the entire current of a circuit may be controlled without a relay circuit, an arm for supporting said movable contact, a yoke mounted on said base, said arm being pivoted to said yoke, a temperature influenced bellows carried by said yoke and acting upon said arm for moving the same, a spring coun teracting the bellows and means for adjusting the tension of said spring, said means comprising a washer against said spring. a cam surface on said washer, a lever pivoted at a point spaced from the axis of said washer and a cam surface on said lever for coacting with the cam surface on the washer.

6. A device of the kind described comprising a base, a yoke supported thereby, a switch arm pivoted to said yoke, a pin extending from said switch arm, a notched washer, a spring on one side thereof, a bellows on the other side thereof, the notch in said washer 'receiving said pin whereby expansion and contraction of the bellows will move said switch arm.

7. A device of the kind described comprising a base, a yoke supported thereby, a switch arm pivoted to said yoke, a pin extending from said switch arm, a notched washer, a spring on one side thereof, a bellows on the other side thereof, the notch in said washer receiving said pin whereby expansion and contraction of the bellows will move said switch arm and cam means for varying the adjustment of said spring for changing the setting of said device.

8. A device of the kind described comprising a base, a yoke supported thereby, a switch arm pivoted to said yoke, a pin extending fromsaid switch arm, a notched washer, a spring on one side thereof, a bellows on the other side thereof, the notch in said washer receiving said pin whereby expansion and contraction of the bellows will move said switch arm, a second washer against the free end of said spring, a post extending from said base, said second washer being slidably mounted thereon.

9. A device of the kind described comprising a base, a yoke supported thereby, a switch arm pivotedto said yoke, a pin extending from said switch arm, a notched Washer, a spring on one side thereof, a bellows on the other side thereof, the notch in said washer receiving said pin whereby expansion and contraction of the bellows will move said switch arm, a second washer against the free end of said spring, a post extending from said base, said second washer being slidably mounted thereon and means for locking said washer at any position thereon, said means comprising a lever having cam means for coacting with said second washer.

10. A device of the kind described comprising a base, a yoke supported thereby, a switch arm pivoted to said yoke, a pin extending from said switch arm, a notched washer, a spring on one side thereof, a bellows on the other side thereof, means for adjusting said bellows relative to said yoke, the notch in said washer receiving said pin whereby expansion and contraction of the bellows will move said switch arm, a second washer a ainst'the free end of said spring, a post extendin from said base, said second washer being slidably mounted thereon.

11. A device of the kind described compris-, ing a base, a yoke supported thereby, a switch arm pivoted to said yoke, a pin extending from said switch arm, a notched washer, a spring on one side thereof, a bellows on the other side thereof, the notch in said washer receiving said pin whereby expansion and contraction of the bellows will move said switch arm, a second washer against the free end of said spring, a post extending from said base, said second washer being slidably mounted thereon, means for locking said washer at any position thereon, said means comprising a lever having cam means for coacting with said second washer, and a scale associated with said lever for indicating the desired temperature at which the device is to be set for operation.

12. In a temperature controlled device, a movable arm, a temperature influenced bellows acting upon said arm for moving the same, a spring counteracting the bellows and means for adjusting the tension of said spring, said means comprising a member engaging said spring, said member being slidable and non-rotatable and cam mechanism for moving said means.

Des Moines, Iowa, December, 1927.

ALBERT PENN.

Images