US2029551A

US2029551A - Temperature control device for furnaces

Info

Publication number: US2029551A
Application number: US741122A
Authority: US
Inventors: Robert M Baker
Original assignee: Individual
Current assignee: Individual
Priority date: 1934-08-23
Filing date: 1934-08-23
Publication date: 1936-02-04
Anticipated expiration: 1953-02-04

Description

1936. IR. M. BAKER TEMPERATURE CONTROL DEVICE FOR FURNACES 2 Sheets-Sheet 1 Filed Aug. 23, 1934 Feb 49 39360 R. M. BAKER TEMPERATURE CONTROL DEVICE FOR FURNACES F l ug- 5, 1934 2 Sheets-Sheet 2 Patented Feb. 4, 1936 UNITED STATES PATENT OFFICE TEMPERATURE CONTROL DEVICE FOR FURNACES '7 Claims.

This invention relates to temperature control devices for furnaces, but particularly to an automatic device for controlling one or more dampers in accordance with the heat generated by the furnace.

An object of this invention is to produce a new and improved furnace temperature control or regulatonwhich can be initially or from time to time adjusted in a simple manner to the temperature desired, and will thereafter operate automatically to obtain a substantially uniform temperature of a predetermined degree. Another object is to produce a furnace temperature regulator which has the novel features of construction, operation and arrangement hereinafter described.

Further objects and advantages will hereinafter appear, and, for purposes of illustration, an embodiment of the invention is shown on the accompanying drawings, in which:

Figure 1 is a fragmentary side elevational view of a furnace with a portion of the casing and body of the furnace broken away to show the interior thereof equipped with my new temperature regulator;

Figure 2 is a transverse sectional view on the line 2-2 of Figure 1 showing the baffle construction of the smoke consumer;

Figure 3 is an enlarged sectional view on the line 33 of Figure 1 showing the thermally actuated rocking bar;

Figure 4 is a sectional View on the line 4--4 of Figure 3;

Figure 5 is an enlarged fragmentary front elevation of an upper end portion of the furnace casing showing the manual control for the thermally actuated bar; and

Figure 6 is a fragmentary side elevational view of the upper end'of the furnace casing showing the blower control.

The illustrated embodiment of the invention comprises a furnace body or shell ll] of the usual steel construction, or of such material, as to expand or contract thermally, and enclosing the body I is a casing or jacket ll of sheet metal, or other suitable material.

Mounted on the upper end of the furnace body is a pointed fulcrum l2 on which rests a lateral extension l3 of a bar M, which extends transversely of the upper portion of the casing I I. The lateral extension [3 is preferably disposed centrally of the bar 14 and the bar is rockable in response to thermo-expansion or contraction of the furnace body Ill. The opposite ends of the bar [4 are considerably reduced in size and are rounded, one end being rockably mounted in a plate l having a stud l6 suspended from a bracket IT, a nut l8 adjustably holding the plate l5 in the desired position. Initially, the vertical position of the plate [5 is adjusted by turning the nut [8.

The opposite rounded end of the bar I4 is 5 mounted in and free to rock relative to one end of an adjusting arm I9. The arm I9 is pivoted at 20 in an embossed portion of a bracket plate 2|, which is secured to the outside of the casing II. The opposite end of the arm [9 extends outside of 10 the casing ll through a vertically elongate slot 22. Extending laterally from the arm I9 is a flange or tooth 22 which may be moved into selective engagement with one of the notches 23 on a calibrated indicator plate 24. It will be noticed that this plate is calibrated from zero to seventy degrees, and the arm [9 is adjusted with respect to this plate in accordance with the temperature of the air outside of the building. For example, if the outside temperature is 25 F. the arm I9 is adjusted so that the tooth 22 is inserted in the notch corresponding to the 25 calibration on the plate 24, and, as will hereinafter appear, this adjusts the thermally actuated bar 14 properly to maintain a suitable temperature within the room 25 to compensate for the cooler outside temperature.

Fixed to the bar l4 between the lateral extension l3 and one end of the bar, is an arm 25 to the outer end of which is pivoted a depending link 26. The lower end portion of the link 26 is provided with a series of holes 21 selectively to receive a bolt for connection to an arm 28, the inner end of which is provided with a weight 29. The opposite end portion extends through the case I I and is pivotally mounted at 30, and the free end thereof is connected by a chain 3| to a draft damper 32 of the usual form disposed at the lower part of the furnace, in this instance being mounted on the door 33 of the ash pit. The arm 28 is also connected by a slotted link 34 to a door 35, which controls the passage 36 leading to a vertically disposed bell-shaped smoke consumer 31 in which is disposed a core 38 having a series of radial baflles or blades 39 suspended in place by a bolt 40.

It will be understood that when the door 35 is open, air is drawn therethrough and broken up by the baffle plates 39 to effect more complete combustion of fuel within the combustion chamher. It will be understood that the weight 29 is sufficient substantially to compensate for the weight of the

dampers

32 and 35 in order to maintain substantially a balanced condition and to enable slight vertical movement of the arm 26 to effect the desired opening or closing movement to these dampers.

If desired, a blower may be provided for forcing air through the furnace, and thereby increase the circulation of air through the furnace. Such blower is not shown on the drawings, but any well known type of electrically driven blower may be used for this purpose and may be operated by anarm 4|, which is fixed at one end to the end of the bar 4 adjacent the bracket plate IS. The opposite end of the arm 4| may be L-shaped and is formed with a looped end to engage a switch arm 42. Upon rocking movement of the arm I 4 in one direction, the arm 4| will be moved in such manner as to move the switch arm 42 to close an electric circuit for energizing the blower, and actuation in the opposite direction will move the switch arm 42 to open the blower circuit.

In operation it is apparent that the expansion or contraction of the furnace body I!) operates to rock the bar l4, and this movement is transmitted by links and levers to the

doors

32 and 35, which may be concommitantly opened or closed to increase or diminish the draft to the combustion chamber. The amount of such movement, it is apparent, is controlled by the adjustment of the control arm I9, and such adjustment is dependent upon the outside temperature.

It is to be understood that the above description is to be given by way of illustration and not of limitation, and numerous changes in details of construction and operation may be effected without departing from the spirit of the invention, especially as defined in the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. A temperature controlling device for a furnace provided with a furnace body, a housing enclosing said body and a draft damper, said device comprising a fulcrum on the top of said body responsive to thermal expansion or contraction of said body, a bar extending across said housing, a pivotal mounting for opposite ends of said bar enabling axial turning movements thereof, a lateral extension on an intermediate portion of said bar resting on said fulcrum, lever and link means connecting said bar with said damper for actuating same upon turning movements of said bar, and means for raising or lowering one end of said bar for predetermining the action thereof.

2. A temperature controlling device for a furnace provided with a furnace body, a housing enclosing said body and draft damper, said device comprising a fulcrum on the top of said body responsive to thermal expansion or contraction of said body, a bar extending across said housing, a pivotal mounting for opposite ends of said bar, a lateral extension on an intermediate portion of said bar resting on said fulcrum, lever and link means connecting said bar with said damper for actuating same upon rocking movements of said bar, an arm pivoted adjacent one end and engaging said bar at such end, the opposite end of said arm extending outside of said housing to enable same to be adjusted for predetermining the action of said bar.

3. A temperature controlling device for a furnace provided with a furnace body, a housing enclosing said body and a draft damper, said device comprising a fulcrum on the top of said body responsive to thermal expansion or contraction of said body, a bar extending across said housing, a pivotal mounting for opposite ends of said bar, a lateral extension on an intermediate portion of said bar resting on said fulcrum, lever and link means connecting said bar with said damper for actuating same upon rocking movements of said bar, an arm pivoted adjacent one end and engaging said bar beyond the pivotal point thereof, the free end of said arm extending outside of said housing, a plate on said housing calibrated in degrees of temperature, and means on said plate for receiving the free end of said arm in selective position.

4. A temperature controlling device for a furnace provided with a furnace body, a housing enclosing said body and a draft damper, said device comprising a fulcrum on the top of said body responsive in vertical movement to changes in thermal conditions of said body, a bar extending across said housing, a pivotal mounting for opposite ends of said bar enabling axial turning movements thereof, a lateral intermediate extension on said bar resting on said fulcrum, and lever and link means connecting said bar with said dampers for actuating same from turning movements of the former.

5. A temperature controlling device for a furnace provided with a furnace body, a housing enclosing said body and a draft and smoke consumer dampers, said device comprising a fulcrum on the top of said body responsive to thermal expansion and contraction of said body, a bar extending transversely of said housing, a mounting for opposite ends of said bar to afford axial turning movements thereof, a lateral extension on said bar resting on said fulcrum, and operative connections between said bar and dampers to actuate same from rocking movements of the former.

6. A temperature controlling device for a furnace provided with a furnace body, a housing enclosing said body and a draft damper, said device comprising a fulcrum on the top of said body responsive in vertical movement to changes in thermal conditions of said body, a bar extending across said housing, a mounting for opposite ends of said bar to afford turning movements thereof, a lateral intermediate extension on said bar resting on said fulcrum, and lever and link means connecting said bar with said dampers for actuating same from turning movements of the former, said lever and link means including a counterbalance for said damper.

7. A temperature controlling device for a furnace provided with a furnace body, a housing enclosing said body, a draft damper and an electric blower control, said device comprising a fulcrum on the top of said body responsive to thermal expansion and contraction thereof, a bar extending transversely of the upper end of said housing, a mounting for said bar affording axial rocking movements thereof, a lateral intermedlate extension on said bar resting on said fulcrum, and link and lever means operatively connecting said bar and said damper and electric blower control for actuating the latter from rocking movements of the former.

ROBERT M. BAKER.