US2301383A - Heating system and control means therefor - Google Patents

Description

Nov. 10, 1942.

E. .1. DILZLMAN TROL MEANS THEREFOR Filed Feb. 5, 1940 HEATING SYSTEMS AND CON Patente-d Nov. 10, 1942 Earnest J. Dillman,

troit Lubricator HEATING SYSTEM AND CONTROL MEANS THEREFOR Detroit, Mich., assigner to De- Company, corporation of Michigan Detroit, Mich., a

Application February 5, 1940, Serial No. 317,304

(Cl. 20G- 122) 25 Claims.

My invention relates generally to control devices and more particularly to a room thermostat for controlling the temperature of an enclosed space.

One of the objects of my invention is to provide means for controlling a heating apparatus thereby to maintain a predetermined temperature within an enclosed space.

Another object is to provide means for changing the setting of the apparatus for maintaining a predetermined lower space temperature.

Another object is to provide a manually operable means for rendering the setting changing apparatus ineffective.

Another object is to provide means for supplying additional heat to the thermostatc blade to compensate for overrun of the heating apparatus, which would unduly raise the temperature of an enclosed space.

A further object of the invention is to provide a new and novel temperature controlling apparatus which is simple in operation and economical to manufacture.

The invention consists in the improved system and the construction and combination of parts comprising the same, all as will be more fully described hereinafter and the novelty of which will be particularly pointed out and distinctly claimed.

In the accompanying drawing, to be taken as a part of this specification, I have fully and clearly illustrated my invention, in which drawing- Figure 1 is a view in front elevation of the thermostat with a portion of the cover broken away;

Fig. 2 is a view substantially along the line 2-2 of Fig. l and looking in the direction of the arrows;

Fig. 3 is a view substantially along the line 3-3 of Fig. 1 and looking in the direction of the arrows;

Fig. 4 is a partial view in rear elevation showing the adjusting mechanism:

Fig. 5 is a partial View in side elevation showing the means for securing the thermostat base to the mounting bracket;

Fig. 6 is a view substantially along the line 6-6 of Fig. 1 and looking in the direction of the arrows;

Fig. '7 is a partial view in top elevation showing certain of the elements of the thermostat;

Fig. 8 is a partial view in side elevation showing the night turn-down switch; y

Fig. 9 is a diagrammatic view of the apparatus connected to a heating system;

Fig. 10 is a view of the heater switch blade, and

Fig. 11 is a partial view of a modified form of the thermostatic blade and the carried contact member.

Referring to the drawing by characters of reference, the numeral I designates generally a base or supporting member which is preferably substantially rectangular in form and molded from an insulating material such as Bakelite and the numeral Iu designates generally a cover member cooperable therewith. A fulcrum or bearing post 2 has one end secured within an aperture 3 extending through and located adjacent the lower end 4 of the base member I, and has its other end extending outward from the front face 5 of the base member I and into the space enclosed by the cover member I a. An elongated, plate-like member 6 extends adjacent to and parallel to the face 5 and has at one end portion 6 a pair of spaced ears or anges -I, 8 connected by a vertical portion 9. The ears 1, 8 have aligned apertures which receive and journal about the post 2 to secure the member 6 for rotational movement in a plane parallel to the face 5. The member 6 extends longitudinally of the member I and the other end I0 of the member 6 terminates adjacent the upper end II of and preferably to the right of the longitudinal centerline of the member I. Journaled Within a tapered aperture I2 adjacent the end II, and substantially on the longitudinal centerline of member I, is a tapered portion I3 of a cam I4 which substantially fits the aperture I2. The cam I4 is positioned adjacent the front face 5 of the base member I, and has a metallic insert or shaft I-'Ia molded thereinto which extends through the portion I3 and outwardly from the rear face I5 of the base member I and is threaded as at I4". A range adjusting or Calibrating screw I 6 is screw-threaded through the side arms of a hook-shaped portion IIa of an upturned flange I 1 positioned at the end I0 of the member 6, and engages the face of the cam I 4. The side arms of the hook-shaped portion I6al are preferably held under a slight tension by the screw I6 so that the screw is frictionally held in adjusted position. A helically coiled spring member I8 is positioned concentric with the post 2 intermediate the spaced ears 1, 8 and has one end portion I9 positioned within an aperture in an outwardly projecting boss 20 of the base face 5 and has its other end portion 2I extending longitudinally of and engaging an upturned flange portion 22 of the member 6. The spring member I8 acts to urge the plate-like member 6 in a counterclockwise direction (see Fig. 1) to maintain the screw I6 in constant engagement with the face of the cam I4 so that rotational movement of the shaft I4a can act through the cam I4 to move the member 6 in accordance with the setting,r of the shaft |48. The portion 22 has a lead wire receiving lug 22, the function of which will be set forth hereinafter.

The member 6 has intermediate its ends 6ut and I0, a rearwardly projecting lug 23 which ex- Ulli tends through a slot 24 in the base member I so that a head portion which is normally spaced slightly rearwardly of the rear face I5 cooperates with the face I5 to prevent accidental movement of the member 6 away from the front face. A metallic supporting member 26 is positioned to the left of the longitudinal centerline of the meinber I and has a horizontal portion 21 extending longitudinally of and held to the base member I by means of rivets 28, 28a. The rivet 28 acts to electrically connect the member 26 to a binding post or screw 28b secured to the face I5. The member 26 has an upturned flange portion 29 having an L-shaped, offset extending portion having its short leg 38al perpendicular to the portion 29 and its longer leg 3i)b parallel to the portion 29. A shoulder 3I is formed at the intersection of the leg 38 with the portion 29, and a U-shaped permanent magnet 32, which is preferably Alnico for high magnetism, is held with its poles spaced in a plane normal to the face 5 and facing toward the longitudinal centerline of the member I. An inturned lug 33 of the vertical portion 29 rigidly clamps the magnet 32 against the leg 3U.

Spaced from the shoulder 3| and toward the end 4 of the base member I, the supporting member 26 has an upstanding ear or lug 34 to which is secured one end portion of a iiexible spring contact carrying blade 35, which blade extends longitudinally of the base member I and between poles of the magnet 32, with the other end portion parallel to and laterally spaced from the leg 30h. The blade 35 in its inert state iiexes toward the leg 30b and away from the member 6, and is positioned or exed toward the member 6 by means of an adjustment screw member 36 which in this instance is screw-threadedly secured to the leg 3Ilb and has one end thereof engaging the blade 35. A contact member 31 is rigidly secured to the blade 35 and is positioned intermediate the poles of magnet 32, its position relative to the pole end faces being determined by the member 36 which thereby acts to determine the temperature differential at which the apparatus cperates.

A bimetallic strip or blade 38, which may be slightly tapered, has its wider end portion 39 secured to the vertical portion 9 of the plate-like member 6 and the other or narrower en-d portion 40 ofthe bimetallic strip 38 terminates substantially in the plane of the magnet 32. A substantially rigid metallic strip 4I, which in this instance is about onethird the length of the strip 38, has one end portion 42 secured to the bimetallic end portion 40 and has its other end portion 43 extending toward the lower end 4 of the base member I, the portion 43 being spaced from the strip 38 toward the blade 35. The strip end portion 43 has a lug or terminal 45 extending downward therefrom and toward the strip 38 to serve as a. terminal for a exible lead wire. One end portion 46 of a flexible contact carrying blade 41 is secured to the portion 43, as by means of rivets. The other end portion 48 of the blade 41 is located intermediate the portion 40 and the contact member 31 and has secured thereto as by riveting, a contact member 49 which is cooperable to engage with the contact member 31 to control an electrical circuit. A pair of projections or ears extend outward from the strip end portion 42 to form an armature 49l which cooperates with the magnet 32 to cause the contact members 31, 49 to make and break the electrical circuit controlled thereby with a quick action. This quick action is partly made possible by the flexibility of the bimetallic strip 38 and partly by the ilexibility of the blade 41. A vibration dampening leaf spring 50 extends spaced from and longitudinally of the blade 41 and has one end secured to the end portion 46, and has an offset bent portion 5I at its other end which normally engages the blade 41 approximately one-third of the dis tance between the contact member 49 and the blade end portion 46. While the contact members 31, 49 are in engagement, the spring bent portion 5I is separated from the blade 41 and the riveted portion of the contact member 49 is in engagement with the strip end portion 42. Upon disengagement of the contact members 31, 49 the blade 41 will flex outwardly away from the end portion 42 and into engagement with the bent portion 5I of the spring 50. Engagement of the portion 5I by blade 41 acts to dampen vibration of the contact member 49 thereby to prevent any accidental engagement upon opening of the contact members 31, 49.

Projecting rearwardly from the base member face I5 and adjacent the end portion II and the shaft threaded portion I4b is a lug 52 which is preferably molded integral with the base member I. A plate member 53, which is positioned against the face I5 and concentric with the shaft I3, has a plurality of apertures therethrough, one of which receives the lug 52 to secure the member 53 against rotation and another of which loosely receives the shaft I4. The plate member 53 is preferably located back of the base member I and so that it can not be seen when viewing the front face 5, with the exception of a nger or pointer 54 which projects upward beyond the base member end II and which serves as an indicator. A disc-shaped dial plate 55 is positioned against the member'53 concentric with the shaft I4a which is received within a central aperture extending through the dial plate 55. The dial plate 55 is rigidly held against a shoulder on the shaft I4a by means of a nut 56 threaded on the shaft portion I4J. An arc-shaped slot in the dial plate 55 which may be of 180 as shown receives the lug 52, and cooperates therewith to limit rotation of the dial plate 55. Projecting radially outward from the circumference of the dial plate 55 is an extending portion or knob 51 which is preferably so positioned that the pointer 54 and knob 51 are in radial alignment when the instrument is set for normal operation. Suitable indicia inscribed on the plate 55 cooperates with the pointer 54 to indicate the temperature at which the contact members 31, 49 will engage to complete an electrical circuit therethrough. The dial plate 55 is frictionally held against unwanted rotation by a leaf spring 58 having one end portion held against the base member face I5 by means of a screw 59 having its head positioned against the base member face 5 and extending through the base member I so that the other or threaded screw portion will screw-threadedly engage and hold the spring 58.

Pivoted to the rivet 28 is one end of a platelike lever member 60 which has secured to its other end portion a heater carrying member 6I, preferably made of a strip of Bakelite. A pair cf clips 62, 63 are riveted one at each end portion of the member 6I and to the outer face thereof for receiving the end portions cf a cartridge type cylindrical heater'64. The clip 62 is electrically connected to the member 60 through the rivet which secures the clip 62 and members 60, 6I together. The clip 63 is secured to the member 6I and electrically connected by means of a .rivet 61 to a plate-like member 66 which underlies one end portion of the member 6 I. The platelike member 66 has an upturned ange or ear 65 which extends perpendicular to the member' 8| and beyond the outer face thereof. A plate-like member 68 is rigidly secured against the base member face and within a conforming recess of an embossed surface 68 by a rivet which also serves to connect electrically the plate member 88 to a binding screw or post 89 secured to the base member face I5. The plate member 68 has a portion 10 bent upward into a position substantially perpendicular to the face 5 and parallel to the ear 86a. A screw 1I extends through an aperture in the portion 10 and has its head end abutting the face of the portion 19 away from the ear 66a. The threaded portion of the screw 1I is screw-threaded into a threaded aperture within the ear 68n aligned with the aperture in portion 1|). A helical coil compression spring 12 arranged concentric with the screw 1I has one end abutting the portion 10 and its other end abutting the ear B6 so that the member 65 may be pivoted about the rivet 28 by the screw 1I and thereby positioned relative to the bimetallic strip 38. A pointer 14 which is integral with the member B6 cooperates with suitable indicia on the member G8" to indicate the position of the heater 64 relative to the bimetallic strip 38.

Heat from the heater 64 is radiated directly to the strip 38 and is also transferred to the strip 38 through an arm or L-shaped portion 15 of the ear 1 and through the vertical portion 9 which serves as a heat conducting member. One leg ol the L-shapcd portion is spaced from and overlies the heater 64 and is tapered so that as the heater 64 is moved away from the strip 38, less heat will be conducted through the portion 15 to the strip 38.

For purposes of night turndown, so that the strip 38 will act to close the contact members 31, 49 at a predetermined lower surrounding temperature, there is provided a heater element 89 which is positioned adjacent to and to the right of the bimetallic strip 39, and is spaced from the front face 5. The heater preferably comprises a strip of Bakelite SI, or other electrical insulat ing material, which is not affected by temperature and is clamped at either end to metalli-c spacer members 82, 83 by means of screws 82a, 83e.

The spacer member 83 has a reduced portion extending through an aperture in the base member I and has a shoulder formed at the intersection of the reduced portion with the normal diameter portion which abuts the face 5 and positions the spacer member 83 relative to the member I. The reduced diameter portion extends beyond the face 5 and extends through an aperture in a plate 84 and the end portion is peened or riveted over to secure the member 83 within the base member aperture and the plate 84 to the face I5. The plate 84 has a binding screw cr post 85 for securing the thermostat lead wire. The spacer member 82 is substantially a U-shaped member having one of its leg portions turned outwardly, as at 86, and apertured to receive a rivet 88a which extends through an aperture i1 the base member I and an aperture in a binding post or plate 81. rigidly secure plate 81 and member 8 2 to the base, member I The end cf the other leg portion of the member 82 is received within an indent in the face 5 and is so positioned therein that when the screw securing the strip 8I to the spacer mem- The rivet is peened over to ber 82 is rotated, the spacer member is held against rotation.

The leg portion which is received within the indent has a horizontal offsetting portion which is apertured to receive a binding screw 88. A coil of resistance wire 89 is wound around the strip 8| and has one end thereof secured to a clip which is positioned beneath the screw 83a and the other end of the wire 89 is secured to contact member 90 which is carried by the strip 8| intermediate the coil of wire and the member 83, and on the under surface thereof facing the face 5 of the member I. A switch blade 9|, which may be a piece of flexible, resilient, current conducting metal, has one end secured intermediate the strip BI and the spacer member 82 by the screw 82e. The blade 9I extends substantially parallel to and beneath the strip 8I so that it underlies the contact member 99 and cooperates therewith to control an electrical circuit. The blade 9| has an offset portion 92 which is bent downwardly toward the base member face 5 and cooperates therewith to limit the movement of the blade 9| in its opening direction and also serves as a cam face for cooperating with a slide member 98 carried by the cover member If. The member 93 is slidable longitudinally of the member In parallel to the face 5 and along the cam face 92 to open and close the circuit to the heater element 80. A flange portion 94 of the member 93 is located intermediate the outside surface of the cover member Ia and the under surface of a cap 95 carried by the member' I". A serrated external portion 96 extends externally of the cap 95 through a slot 91 so that the switch may be operated manually externally or thel apparatus. The cap 95 preferably contains suitable legendary matter so that the setting of the switch is clearly evident to persons operating the apparatus.

A mounting bracket |09 is preferably formed from a piece of plate stock haring flanged, longitudinal edge portions IIII and hook-like portions I02 which extend outwardly and upwardly from: each flange portion IUI. The base member I has a pair of oppositely disposed side wall recesses 13 which form shoulders H14. The recesses |93 receive the hook-like portions |92 and the shoulders |04 cooperate therewith. to removably secure the member I to the bracket Hi8. With this ofnstruction, the thermostat lead wires may be connected to the apparatus, and the bracket H18 secured to the room wall. prior to the securing rf the base member I to the bracket |90 so that a completely concealed mounting is obtained. and one in which the cover member Ia nerd not be removed during the installation of the apparatm. This is particularly advantageous beca"se it eliminates the danger of accidental damage to tho delicate operating parts of the thermcstatie epparatus.

There is but one lead wire I05 within the instrument, and this connects the binding scew 88 to either the lug 22a or the lus7 45, depending upon the operating characteristics desired. If the instrument is to be used on low amperag-e equipment which is generally the cesn in low voltage circuits, it is preferable to secure the lead wire |05 to the lug 22" to minimize the resistance to movement of strip 38 and use the strip 38 a current conducting member. However. if the instrument is to be used on relatively high amperage equipment, which is generally the case in higher voltage circuits, the lead wire is connected to the lug 45 so that the heating effect of the loro current flowing through the strip 38 is eliminated.

The apparatus is connected into a control system by means of suitable lead wires. The binding post 81 is connected by the lead wire |25 to one side of the secondary of a transformer |26. The other side of the secondary is connected by a lead wire |21 to an electrically operated heat supplying means |28 and by a lead wire |29 to one contact of a time switch |30. A lead wire |3| connects the lead wire |29 with a binding post 69 so that the transformer secondary is connected directly to the means |28, time switch |30, and anticipatory heater 64. The other side of the means |28 is connected by a lead wire |32 to binding post 28b and the other side of the time switch |30 is connected by a lead wire |33 to the binding post 85. The primary of the transformer |26 is supplied with electrical energy through lead wires |34.

Fig. 11 shows a modification of my apparatus. The thermostatic blade 38a has an offset end portion 40 which carries one edge portion of a non-heat-conducting, non-electrical-conducting plate-like member |40 which may be a piece of Bakelite. The end portion 42a of the rigid strip 4|n is secured to the opposite edge portion of the member |40. A flexible lead wire |4| has one end (not shown) connected to the binding screw 88. The other end of the wire |4| is connected, as at |42, so that it makes good circuit with the blade 41a and therethrough to the contact member 49h. The wire |4| is clamped, as at |43, so that the wire is rigidly supported for movement with the blade 38t without mechanical strain at the connection |42. With this construction no current flows through the bimetallic blade 38 and therefore the blade is not affected by any internal heating effects due to the innate resistance of the blade to current flow. Furthermore, by electrically isolating the blade 38 and platelike member 6 any capacity effect at open circuit condition between the parts electrically connected with the contact member 31 and the blade 38n and member 6 is eliminated.

When the contact members 31 and 49b are in engagement and current is flowing therethrough a certain amount of heat is generated due to contact resistance. At circuit closed position the contact member 49b is in engagement with the rivets securing the portion 42 to the member |40` but the member |40, due to its resistance to heat flow, acts to prevent any appreciable conduction therethrough to the sensitive bimetallic blade 38a.

The blade 38a therefore remains responsive to the temperature of the surrounding air. With this construction, the apparatus may be utilized to control circuits of relatively high currents and/or high voltages without a detrimental effect on the accuracy of the blade 38, It is seen that the modification has certain advantages over the construction shown in the other figures.

The operation of my apparatus is as follows: Suitable lead wires are connected as hereinbefore described to the binding screws 28h, 69, 85 and 81. When the slide member 93 is moved to off position or the time switch |30 is in open circuit position, the apparatus then acts to control an electrical circuit from the transformer |26, lead wire |25, binding post 81, its associated rivet, spacer member 82, lead wire to lug 22* then through strips 38 and 4|, blade 41, contact members 49, 31, blade 35, binding post 28b through its associated rivet, lead Wire |32, means |28, and lead wire |21. A circuit from the transformer |26 through the same path to blade 35 is also controlled by the contact members 49, 31, but then the latter circuit goes through lever member 60, clip 62 and its associated rivet, heater 84, clip 63 and its associated rivet, screw 1|, member 68, binding post 69 through its associated rivet, lead wire 3| and lead wire |29 to the transformer |26. In this manner the heater 64 is energized each time the contact members 31, 49 are closed so that the heater may anticipate the increased room temperature in the well known manner, and its heat output is independent of the current flowing through the means |28. Upon movement of the slide member 93 downward or to on position, the blade 9| engages contact member 90 and a circuit is completed from the transformer |26, through lead wire |25, binding post 81, its associated rivet, spacer member 82, blade 9|, contact member 90, wire 89, spacer member 83, binding post through its associated rivet and to the time switch 30. Upon closure of the time switch |30 the circuit is completed through the lead wire |29 to the transformer |26. The heater element 80 so energized acts to heat the strip 38 so that it is maintained for example at 9 F. above ambient temperature, thereby acting to temporarily maintain the room temperature 9 F. below the setting of the dial plate 55. Upon movement of the slide member 93 to off position, the heater element 80 is deenergized and the strip 38 acts to control the contact members 31, 49 normally irrespective of the switch |30.

It is to be noted that the disclosed construction is simple and economical for quantity manufacture, eliminates all inserts which heretofore were molded within the base member thereby greatly decreasing the manufacturing costs thereof. The disclosed construction also eliminates the need for an .extra night temperature sensitive blade, or for a mechanical means to alter the normal daytime setting of the day temperature sensitive blade. It may furthermore be noted that the switch blade 9| may be omitted and the terminals of the coiled heater wire 89 connected directly one to each of the spacer members 82, 83 and the time switch |30 act to control the energization of the heater 80 thereby rendering the night turn-down entirely automatic without any means to provide for abnormal operation.

The preferred embodiment of the device, however, is to have the time switch |30 energize the heater 80 at a regular predetermined time each evening, and to deenergize the heater each morning at a regular predetermined time. The manually operable slide member 90 is then utilized as a means for preventing operation of the heater 80 upon those occasions when it is desirable to maintain normal operation of the thermostat during the periods when the heater 80 would normally be energized by the time switch |30. The member 90 thus enables the operator to rbduy and simply render the time switch |30 ineffective to set the thermostat for night operation, upon certain occasions, without interfering with the normal operation of the time switch per se or changing the setting of the dial plate 55 to compensate for the effect of the heater 80.

What I claim and desire to secure by Letters Patent of the United States is:

1. In an apparatus of the character described, a base member, a movable supporting member pivotally supported at one end thereof to one face of said base member, a bimetallic element secured at one end portion to said supporting member, a rigid member secured to the other end portion of said bimetallic element and having its free end extending toward said element one end, a flexible carrying member secured to the free end of said rigid member and having a portion extending toward said element other end portion, a contact member carried by said fiexible member at said iiexible member portion, said iiexible member being operable to allow relative movement between said contact member and said element, and adjusting means on said base member on the face opposite to said one face, said adjusting means having a portion extending 'through said base member and operable lto vary the temperature at which said contact .'member will complete an electric circuit.

2. In an apparatus of the character described,

base member, a movable supporting member votally supported at one end thereof to one face of said base member, a bimetallic element secured at one end portion to said supporting member, a xed contact member carried by said base member on said once face, a rigid member carried by the other' end portion of said bimetallic element, a flexible contact carrying member carried by said rigid member and having a portion adjacent said element other end portion, a movable contact member carried by said flexible member at said flexible member portion, said flexible member' being operable to allow relative movement between said movable contact member and said element, adjusting means on said base member on the face opposite to said one face, said adjusting means having a portion extending through said base member, said extending portion having a cam operable upon movement of said adjusting means to engage and to move said supporting member to vary the temperature at which said movable contact member will engage said fixed Contact member, and means tending to follow said movable Contact member to dampen vibration of said movable. contact member subsequent to disengagement of said contact members.

3. In an apparatus of the character described, a base member, a movable supporting member pivotally supported at one end thereof to one face of said base member', a bimetallic element secured at one end portion to said supporting member, a xed contact member carried by said base member on said one face, a rigid member carried by the other end portion of said bimetallic element, a flexible contact carrying member carried by said rigid member and having a portion adjacent said element other end portion, a movable contact member' carried by said flexible member at said flexible member' portion, said flexible member being operable to allow relative movement between said movable contact member and said element, adjusting means on said base member on the face opposite to said one face, said adjusting means having a portion extending through said base member and operable to vary the temperatur'e at which said movable contact member will engage said fixed contact member, means to dampen vibration of said movable contact member subsequent to disengagement of said contact members, a horse-shoe type permanent magnet having its poles embracing said fixed contact member and carr1ed 'by said base member, and armature means carried by said rigid member and cooperable with said magnetic means to cause said movable contact member to move with a quick action 4. In an apparatus of the character described,

CII

Search iieom a base member, a contact member carried by said base member, a thermostaticelement carried by said base member, a Contact member carried by said element, a heat supplying means, a heat conducting member secured in heat conducting relationship to said element for conducting heat supplied by said heat means to said element and having a portion positioned adjacent said heat means, and means for varying the rate of heat transfer to said element from said heat supplying means.

5. In an apparatus of the character described, a base member, a contact member carried by said base member, a thermostatic element carried by said base member, a contact member carried by said element, a heat supplying means, a heat conducting member for conducting heat supplied by said heat supplying means to said element and having a portion positioned adjacent said heat means, and means for moving said heat supplying means relative to said conducting member portion thereby to vary the rate of heat transfer therethrough from said heat supplying means to said element.

6. In an apparatus of the character described, a base member, a contact member carried by said base member, a thermostatic element carried by said base member, a contact member carried by said element, a heat supplying means, heat conducting means for transferring heat from said heat'I supplying means to said element, said conducting means having a V-shaped portion adjacent said heat supplying means, and means for moving said heat supplying means with respect to said V-shaped portion thereby to vary the rate of heat transfer from said heat supplying means o said element. 7. In an apparatus of the character described,

` a casing, a thermostatic element carried by said casing, a Contact member carried by said casing, a contact member carried by said element and cooperable with said rst-named contact member' to control an electrical circuit, electrical heater means within said casing and disposed in heat exchange relation with said element, a fixed contact member, a movable contact member, iiexible means having a portion thereof rigid with said casing and carrying said movable contact member and operable to urge said movable contact member in one direction, said fixed and said movable contact members being operable to control an electrical circuit to said heater means, and means slidably secured to a wall of said casing and manually movable from external of said casing for iiexing said carrying means in a direction opposite to said one direction thereby to control the operation of said heater means.

8. In an apparatus of the character described, a casing comprising a base member and a cover member, a thermostatic element carried by said base member, a contact member carried by said base member, a contact member carried by said element and cooperable with said first-named contact member to control an electrical circuit, electrical heater means disposed in heat exchange relation with said element and carried by said base member, a fixed contact member carried by said heater means, a longitudinally extending plate-like member underlying said heater means and having a portion cooperable with said xed contact member and operable to control an electrical circuit to said heater means, said cover member being cooperable with said base member to enclose said element and said heater means, and means carried by said cover member, said last-named means having a portion extending through said cover member and being cooperable with said plate-like member to move said plate-like member in one direction and having a portion extending external of said cover member so that said plate-like member may be moved from externally of said casing.

9. In an apparatus of the character described, a casing comprising a base member and a cover member, a carrying member spaced from and secured to said base member within said casing, a contact member carried by said carrying member within said casing, electrical resistance means carried by said carrying member within said casing and having one terminal thereof secured to said contact member, a movable member within said casing and extending adjacent to said carrying member and having a portion thereof cooperable with said contact member to control an electric circuit to said resistance means, and means carried by said cover member for moving said movable member.

10. In an apparatus of the character described, a casing comprising a base member and a cover member, a carrying member spaced from and secured to said base member within said casing, a contact member carried by said carrying member within said casing, electrical resistance means carried by said carrying member within said casing and having one terminal thereof secured to said contact member, a movable member within said casing and extending adjacent to said contact member to control an electric circuit to said resistance means, said movable member having one end portion secured intermediate said base member and said carrying member, and means carried by said cover member and movable substantially parallel to said carrying member for moving said movable member.

11. In an apparatus of the character described, a casing comprising a base member and a cover member, a strip insulating member spaced from and secured to said base member within said casing, a contact member carried by said strip member within said casing, electrical resistance means carried by said strip member within said casing and having one terminal thereof secured to said contact member, a resilient plate-like current conducting member within said casing and extending adjacent to said strip member and having a portion thereof cooperable with said contact member to control an electric circuit to said resistance means, said plate-like member having one end portion secured intermediate said base member and said strip member, said plate-like member having an offset stop portion at its other end portion, said stop portion being engageable with said base member to limit movement of said plate-like member away from said contact member, and means carried by said cover member portion and movable substantially parallel to said strip member for moving said platelike member.

12. In an apparatus of the character described, a base member, an adjustable temperature sensitive element carried by said base member and movable in a plane substantially parallel to said base member, a rotatable member carried by said base member, cam means having a cam face in a plane substantially parallel to said base member and operable by said rotatable member and cooperable with and to regulate the adjustment of said element, said rotatable member extending through said base member, and a manually operable member rigidly secured to said rotatable member and operable to actuate said cam means, said base member having a portion interposed between said manual member and said cam means.

13. In an apparatus of the character described, a base member having an aperture therethrough, a temperature sensitive element carried on one face of said base member through which said aperture extends, a member rotatable in said aperture and having a portion extending beyond said one face and having a portion extending beyond a second face of said base member through which said aperture extends, a cam member secured to said rotatable member rst-named portion and cooperable with said element upon rotation to adjust the operation of said element, a wheel-like member secured to said rotatable member second-named portion and having a portion viewable upon viewing said one face, said wheel-like member having suitable indicia on said viewable portion, a pointer member cooperable with said indicia for determining the setting of said element, and means carried by said wheel-like member and extending radially therefrom, said extending means being constructed and arranged relative to said pointer member so as to indicate the normal setting of said wheel-like member when said extending means is in alignment with said pointer member.

14. In a device of the character described, a base member, a carrying member pivotally supported on said base member, a contact member carried by said base member, a bimetallic blade having one end portion secured to said carrying member, a non-conducting member secured to the other end portion of said blade and positioned adjacent said contact member, a rigid member carried by said non-conducting member, and a resiliently mounted contact member carried by said rigid member and cooperable with said carried contact member to control an electric circuit.

15. In a device of the character described, a supporting member, a switch arm having one end portion carried by said member, an insulating member secured to said arm, a rigid metallic strip member carried by said insulating member, and a resiliently mounted contact member carried by said rigid member, said contact member being engageable with said rigid member to limit movement of said contact member in one directio relative to said rigid member.

16. In a switch mechanism, a pair of longitudinally extending substantially parallel metallic contact carrying members, a contact member carried by one of said members, a second contact member carried by the other of said parallel members and cooperable with said first-named contact member to control an electric circuit, and an insulating member carried by said other parallel member, said second contact member being electrically insulated from said other parallel member by said insulating member thereby to reduce the capacity effect between said parallel members when said contact members are in open circuit position.

17. In an apparatus of the character described, a base member, a temperature sensitive member, means having movement in a plane parallel to and carried by said base member on one face thereof and supporting said sensitive member for movement in a plane parallel to said one Iace, a fixed contact member, a U-shaped permanent magnet carried by said base member on said one face, means having movement in a plane parallel to and carried by said base member on said one face and extending between the poles of said magnet, said last-named means being operable to position said fixed contact member between said magnet poles and adjustably position said fixed contact member relative to the faces of said magnet poles, a movable contact member carried by said sensitive member and cooperable with said fixed contact member to control an electric-circuit, and adjusting means carried by said base member on the face opposite to said one face, said adjusting means having a portion extending through said base member, said extending portion having a cam surface operable upon rotation of said adjusting means to move said sensitive member supporting means parallel to said one face thereby to vary the temperature at which said movable contact member will engage said fixed Contact member.

18. In an apparatus of the character described, a base member, a cont-act member carried by said base member, a thermostatic element carried by said base member' and having a portion engageable with said contact member to complete an electric circuit, a heat supplying means, a heat conducting means extending into relatively close overlying relation to said supplying means and for transferring heat from said heat supplying means to said element, and means for moving one of said means relative to the other of said means so that the rate of transfer of heat to said heat conducting means from said heat supplying means may be varied.

19. In a device of the character described, a base member having an upper and a lower surface, a fulcrum pin carried by said base member at one end portion thereof and extending from and substantially perpendicular to said upper surface, a longitudinally extending lever member fulcrumed on said pin and extending toward the end portion of said base member opposite to said one end portion, said base member having an aperture therethrough opening through said surfaces, said lever member having a rebent portion adjacent said aperture, an adjustment member rotatable in said aperture and having a cam portion parallel to and adjacent to said upper surface, an adjustment pin screw-threadedly secured to said rebent portion and having an end surface portion engaging said cam portion for movement of said lever member in a plane parallel to said upper surface upon rotation of said adjustment member, an elongated bimetallic strip member secured at one end portion to said lever member and extending along said upper surface toward said opposite end portion, a first contact member carried by said bimetallic member at the end portion thereof opposite to said one end portion and having movement relative thereto, a U- shaped permanent magnet carried by said upper surface and having its poles aligned in a plane extending vertically to said upper surface, a second contact member, means positioning said second contact member intermediate said poles and in position for engagement by said first contact member thereby to complete an electric circuit, and an armature member carried by said bimetallic member and cooperable with said magnet to cause said contact members to engage with a quick action, means rigid with said rst contact member and engageable with said armature, member subsequent to engagement of said first contact member with said second contact member thereby to limit the movement of said arma- Search Room ture member toward said magnet to prevent a positive engagement of said armature member with said poles.

20. In a device of the character described, a

ase member having an upper and a lower surface, a fulcrum pin carried by said base member at one end portion thereof and extending from and substantially perpendicular to said upper f surface, a longitudinally extending lever member fulcrumed on said pin and extending toward the end portion of said base member opposite to said one end portion, said base member having an aperture therethrough opening through said surfaces, said lever member having a rebent portion adjacent said aperture, -an adjustment member rotatable in said aperture and having a cam portion parallel to and adjacent to said upper surface, an adjustment pin screw-threadedly secured to said rebent portion and having an end surface portion engaging said cam portion for movement of said lever member in a plane parallel to said upper surface upon rotation of said adjustment member, an elongated bimetallic strip member secured at one end portion to said lever member and extending along said upper surface toward said opposite end portion, a first contact member carried by said bimetallic member at the end portion thereof opposite to said one end portion and having movement relative thereto, a U-shap'ed permanent magnet carried by said upper surface and having its poles aligned in a plane extending vertically to said upper surface, a second contact member, means positioning said second contact member intermediate said poles and in position for engagement by said first contact member thereby to complete an electric circuit, an armature member carried by said bimetallic member and cooperable with said magnet to cause said contact members to engage with a quick action, means rigid with said first contact member and engageable with said armature member subsequent to engagement of said first contact member with said second contact member thereby to limit the movement of said armature member toward said magnet to prevent a positive engagement of said armature member with said poles, and means for adjustably positioning relative to the face of said poles the face of said second contact member which is engaged by said first contact member thereby to determine the movement of said armature member toward said poles.

21. In a device of the character described, a base member having an upper and a lower surface, a fulcrum pin carried by said base member at one end portion thereof and extending from and substantially perpendicular to said upper surface, a longitudinally extending lever member fulcrumed on said pin and extending toward the end portion of said base member opposite to said one end portion, said base member having an aperture therethrough and extending through said surfaces, said lever member having a rebent portion adjacent said aperture, an adjustment member rotatable in said aperture and having a cam portion parallel to and adjacent to said upper surface, an adjustment pin screw-threadedly secured to said rebent portion and having an end surface portion engaging said cam portion for movement of said lever member in a plane parallel to said upper surface upon rotation of said adjustment member, an elongated bimetallic strip member secured at one end portion to said lever member and extending along said upper surface toward said opposite end portion, a first contact member, means resiliently securing said first contact member to said bimetallic member and carried by said bimetallic member at the end portion thereof opposite to said one end portion, a U-shaped permanent magnet carried by said upper surface and having its poles aligned in a plane extending vertically to said upper surface, a second contact member, means positioning said second contact member intermediate said poles and in a position for engagement by said first contact member thereby to complete an electric circuit, an armature member carried by said bimetallic member and cooperable with said magnet to cause said contact members to engage with a quick action, said first contact member having a portion engageable with said armature member subsequent to engagement of said first contact member with said second contact member thereby to limit the movement of said armature member toward said magnet to prevent a positive engagement of said armature member with said poles, and means engageable with and movable with said resiliently securing means upon disengagement of said contact members to dampen vibration of said first contact member.

22. In an apparatus ot' the character described, a base member, a supporting member having a portion held against said base member and having an upturned flange, said flange having one portion and having a second portion bent to form a shoulder with said one portion and having a third portion extending beyond said second portion substantially parallel to said one portion, a U-shaped permanent magnet carried by said supporting member adjacent said shoulder with the poles of said magnet in vertical alignment relative to said base member, said supporting member having a second fiange on the side of said magnet opposite to said third flange portion, a resilient blade member having one end portion secured to said second ange and extending between said magnet poles and overlying said third flange poi'- tion, a contact member carried by said blade member intermediate said poles, and means carried by said third ange portion for positioning the contact face of said contact member relative to the face of said poles.

23. In an apparatus of the character described, a base member, a supporting member having a portion held against said base member and having an upturned flange, said ange having one portion and having a second portion bent to form a shoulder with said one portion and having a third portion extending beyond said second portion substantially parallel to said one portion, a U-shaped permanent magnet positioned adjacent said shoulder with the poles of said magnet in vertical alignment relative to said base member, tab means extending from said first flange portion and locking said magnet in position against said shoulder, said supporting member having a second flange on the side of said magnet opposite o said third flange portion, a resilient blade member having one end portion secured to said second ange and extending between said magnet poles and overlying said third fiange portion, a contact member carried by said blade member intermediate said poles, and means carried by said third flange portion for positioning the contact face of said contact member relative to the face of said poles.

24. In an apparatus of the character described, a plate-like base member, a plate-like supporting member secured in face to face relation with said base member and having an upstanding flange, a U-shaped magnet held against said ange with its poles in vertical alignment relative to said base member, a blade member having one end portion secured to said plate-like supporting member` and extending substantially parallel to the upper face of said base member and intermediate the poles cf said magnet, a contact member carried by said blade member intermediate said poles, means carried by said ange and engageable with said blade member for positioning said contact member relative to the end surfaces of said poles, a plate-like elongated arm member having one end portion pivotally secured to said supporting member and extending therefrom toward one end portion of said base member, a bimetallic strip member carried by said base member and extending from said base member one end portion substantially parallel to said base member upper face, a contact member carried by said bimetallic member and cooper-able with said first-named contact member to control an electric circuit, armature means carried by said bimetallic member and cooperable with said magnet to cause said contact members to break said circuit with a quick action, heater means having heat exchange relation with said bimetallic member and carried by said elongated arm member, and means carried by said base member and operable to pivot said elongated arm member thereby t0 position said heater means relative to said bimetallic member.

25. In an apparatus of the character described, a plate-like base member, a plate-like supporting member secured in face to face relation with said base member and having an upstanding fiange, a U-shaped magnet held against said flange with its poles in vertical alignment relative to said base member, a blade member having one end portion secured to said plate-like supporting member and extending substantially parallel to the upper face of said base member and intermediate the poles of said magnet, a contact member carried by said blade member intermediate said poles, means carried by said fiange and engageable with said blade member for positioning said contact member relative to the end surface of said poles, a plate-likeelongated arm member having one end portion pivotally secured to said supporting member and extending therefrom toward one end portion of said base member, a bimetallic strip member carried by said base member and extending from said base member one end portion substantially parallel to said base member upper face, a contact member carlied by said bimetallic member and coopeiable with said first-named contact member to control an electric circuit, armature means carried by said bimetallic member and cooperable with said magnet to cause said contact member to break said circuit with a quick action, electrical heater means having heat exchange i elation with said bimetallic membeil and carried by said elongated arm member, means carried by said base member and operable to pivot said elongated arm member thereby to position said heater means relative to said bimetallic member, said last named means acting as an electrical conductor for said heater means, and spling clip means holding said elongated arm member in good electrical contact with said supporting member.

EARNEST J. DILLMAN..

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