US1628139A - Thermostatically-regulated incubator - Google Patents

Description

May 10, 1927.

J; v. GI ESLER' THERMOSTATICALLY REGULATED INCUBATOR Filed June 16, 1924 2 Sheets-Sheet l May 10, 1927.

J. V. GIESLER THERMOSTATICALLY REGULATED INCUBATOR 2 Sheets-Shet 2 Filed June 16, I924 present invention,

Patented May 10, 1927.

UNITED STATES PATENT OFFICE.

' JEAN v. GIESLER, or. KNOXVILLE, "TENNESSEE, ASSIGNOR 'ro THE FULTON COMPANY, or KNOXVILLE, 'rnNNnssEn, A CORPORATION or MAINE.

THERMOSTATICALLY-REGULATED INCUBATOR.

Application filed June 16, 1924. Serial No. 720,434.

This invention relates to thermostatically controlled devices, and more particularly to devices of this character for use in regulating the temperature of incubators.

Many different constructions have heretofore been proposed for maintaining anniform temperature in incubators, but devices of this character heretofore proposed have been open to more or less numerous and se rious objections including lack of'accuracy and sensitiveness of cdutrol, lack of facility in assembl and adjustment to enable them to be readily set up and adjusted by unskilled persons, lack of simplicity and economy in construction and operation, etc.

1 It is an object of this invention to provide an incubator with thermostatic mechanism for regulating the temperature of the same which is sensitive and accurate in the maintenance of predetermined temperatures, which is easy to assemble and install so that the incubator may be readily put together and all necessary adjustments easily made by unskilled persons, and which is simple and economical in construction and operation so that it is inexpensive to manufacture and economical in service.

The invention is capable of receiving a variety of'mechanical expressions, one of which, for purposes of illustration, has been shown on the accompanying drawings, but it is to be expressly understood that the drawings are for purposes of illustration only and are not to be construed as a definition of the limits of the invention, reference being had to the appended claims for that pur ose.

Referrlng in detail to the drawings, wherein the same reference characters are employed in different views to designate corresponding parts Fig. 1 is a more or less schematic sectional view illustrating the construction and arrangement of an incubator embodying the ortions being broken away for clearnes's oFillustration;

Fig. 2 is an enlarged axial view of the thermostatically operated valve in the water system; and

Fig. 3 is an enlarged fragmentary view showing the air thermostat and its mounting in axial section.

In the form shown, 10 designates the incubator casing, which ma be of any suitable size and material and 0 any suitable manner'of construction. Within saidincubator casing are disposed'means for heating the same, said means preferably taking the form of one or more coilsof pipe 11 through which is circulated a suitable heating medium, such as hot Water, said coil or coils having inlet connections 12 and outlet connectlons 13 which extend through the wall of the incubator and communicate with a heater 14 at the outside of the incubator. Circulation of the water to and from said heater and through the coil or coils may be effected by a pump, or reliance may be placed upon the thermo-siphon system of circulation.

The'heater14 may be of any suitable construction. The' form shown is of the t pe adapted to be used in conjunction witi a lamp or any other suitable type of burner, and includes an exterior casing 15 of any suitable size, shape and material, an interior annular water tank having inner and outer walls 16 and 17 and also of any suitable size, shape and material, and within said tank an interior flue or chimney 18 which is open at the bottom. Said flue 18 has a smaller diameter than the inner wall 16 of the water tank, while the outer wall 17 of said tank is of less diameter than the diameter of the outer casin 15; hence annular passages 19 and 20 are ormed between the inner flue 18 and the water tank and between the water tank and the outer casing, these passages 19 and 20 constitutin the flue or chimney 18 reverse flues w ereby heated air may be caused to circulate around the entire interior and exterior surfaces of the water tank. Communicating with the water "tank is an expansion tank 21 of any suitable size adapted to provide for changes of volume of the water in the. circulating system upon changes of temperature and also to make up for any evaporation or other loss of water.

In order to regulate the extent to which the heated air or gases passing up the flue or chimney 18 is made to circulate around the water tank to impart heat thereto, and therefore to regulate the extent to which the water is heated, the top of the heater is provided with an opening 22 which may be made of the same diameter as that of the inner wall 16 of the water tank. Cooperating with said aperture 22 is a valve 23 which may take the form of a flat disk corwith responding in shape and size to the aperture 22 and adapted to rest on the top of the heater so as to close saidaperture and cause all of the hot air and gases which rise in the flue or chimney 18 to pass laterally through the space between the top of said flue or chimney 18 and said valve 23, and thence downwardly through the flue 19, through the space between the bottom of the water tank and the bottom of the casing 15, and up through the flue 20, whence the hot air and gases may escape through the aperture 24 provided in the top of the casing.

Valve 23 is preferably operated by a thermo stat and said thermostat is preferably subjected to the temperature of the heated water. In the form shown a T connection 25 is interposed in the upper water line adjacent the outlet from the heater and receives a thermostat 26 of any suitable construction mounted within the lateral aperture of said T connection so that its bulb 27 is subjected to the temperature of the water in the upper water line. The operating stem 28 of said thermostat has a knife edge or point engagement with a rocker 2!) mounted on a knife edge fulcrum 30 in a bracket or brackets 31 extending upwardly from the casing of said thermostat. Rocker 29 is provided with an inverted stirrup 32 through which extends a bar or red 33 suitably held in adjusted position in said stirrup 32 by a set screw 34. Said bar or red 33 is connected to the valve 23 at its opposite end by a chain or other suitable element 35, and constitutes with said rocker 29 a lever by which said valve is operated as the thermostat expands and contracts. To adjust the temperature at which the valve 23 is operated by the thermostat 26 one or more adjustable weights 36 are slidably mounted on the bar or red 33 and retained in adjusted position by any suitable means as a set- .screw 37.

As the thermostat 26 is subjected to the temperature of the water in the upper water line adjacent the outlet from the heater, there will always be more or less circulation of water around the bulb 27 of the thermostat so that said thermostat will respond substantially to the temperature of the water in the upper part of the heater. As the temperature of the water rises, the thermostat, which is preferably of the type employing volatile liquid, will remain inactive owing to the resistance to expansion of the thermostat provided by the leverage of the weight 36. When the predetermined temperature at which the thermostat is'to begin operation is reached, however, the volatile liquid in said thermostat will by vaporization cause an expansion of the thermostat, raising the operating stem 28 to tilt the rocker 29 and its bar or red 33 around the fulcrum 30 of said rocker. Thereby the valve 23 willbe lifted from the to of the heater to open the aperture 22 an permit some of the hot air and gases to escape through said aperture without passing through the reverse lines 19 and 20. As the temperature of the water continues to rise, the thermostat will expand to a greater extent, raising the valve 23 to a higher position and permitting more of the hot air and gases to escape from the heater without passing through the reverse flues 19 and 20. Continued expansion will result in the valve 23 being eventually raised to a point wherein all of the hot air and gases will escape through the aperture 22 without exerting substantially any heating eflect on the water in the tank 14. Hence the temperature of the water is accurately and sensitively controlled from the temperature of the water it elf and the desired temperature may be closely maintained by adjustin the weight 36 on the bar or rod 33 to predetermine the time and extent of operation of the valve 23 by said thermostat.

in addition to the heretofore described means for regulating the ten'iperaturc of the water, means are also provided for regulating the temperature of the air within the incubator casing. Tothis end the upper water line is also provided, intermediate the thermostat 26 and the casing wall, with a valve casing 40 of any suitable construction and provided interiorly in any suitable way with a valve port 41. Cooperating with said valve port is a valve member 42 of special construction which is more particularly shown in Fig. 2. Said valve member at its upper portion is formed as the seg ment of a sphere so as to provide a spherical surface 43 which will contact the valve seat 44. at a relatively flat angle and thereby prevent sticking of the valve member to its seat. Below said spherical portion 4:3, the valve member is provided with a conical extension 45 which by its cooperation with the valve port forms an annular passage that varies in area with the extent to which the valve member is lifted from its seat. Thereby the flow of heating medium through the valve port can be nicely graduated as relatively large movements of the valve member can be produced without entirely opening the valve port. This enables a clo'er regulation of the extent of circulation of the heating medium, because in the case of a disk valve a movement of the valve member equal to one-fourth of the diameter of the port entirely opens said port so that all control of the quantity of heating medium must be efiected within a valve movement not exceeding one-fourth of the diameter of the port. With the present invention, however, the controlling action of the valve may be prolonged to any desired extent and the degree of increased circulation correspondill) ing to predetermined movements can be nicely and accurately regulated.

Valve member 42 is carried and operated by a valve stem 46, and in order to prevent the frictional opposition to movement of the valve which exists when a packing gland'is employed, the valve housing.

is so constructed as to eliminate the necessity for such a gland. As shown, the valve housing is provided with an elongated upwardly extending portion 47 closed at its upper end by a centrally apertured plug 48, the height of said extension 47 being such that the water in the system may never reach the aperture 49 in said plug 48. The valve stem 46 extends loosely through said aperture 49 and in the form shown is threaded at its upper end to receive a clcvis 50 which is connected to a baror rod 51 by means of a pin 52.

To operate the valve 42 a thermostat of any suitable type and construction is mounted within the incubator casing at such a point that it will respond accurately and sensitively to the changes. of temperature within the casing. In the form shown, the thermostat 53 is composed of a deeply corrugated expansible and collapsible tubular wall 54, preferably of resilient metal, and closed at its opposite ends by rigid end walls 55 and 56. If desired, said thermostat may be provided with an interior tubular stop as shown at 57 to limit the collapse of the thermostat and hence the opening of the valve when the thermostat is cold, and a filling opening suitably sealed is shown at 58. This thermostat is also preferably of the volatile fluid type so that the expansion and contraction is effected bv changes in the vapor tension of a suitable liquid contained therein.

While, as respects certain features of this invention, said thermostat may be mounted in any suitable way the preferred construction, which possesses certain advantages as hereinafter pointed out, includes a sleeve 59 which extends through the wall of the incubator casing and is t readed at its lower end as shown at 60. A washer 61 and a lock nut 62 are provided on said lower end for clamping said sleeve fixedly in position by engagement-with the inner surface'of the casing wall. The projection end of sleeve 59 constitutes a thermostat support and provides for axial and rotatable adjustment of the thermostat. To this end a plate 63 is provided with a centrally arranged and interiorly threaded ann'ular extension 64 which is adapted to be threaded on to the lower end of said sleeve 59. Depending from said plate 63 is a suitable spider 65 having an inwardly directed ledge or shoulders on which the stationary end wall 55 of the thermostat 53 may rest. By rotating the plate 63 with the thermostat carried thereby upon the threaded end 60 of the sleeve 59, the thermostat may be raised or lowered with respect to said sleeve 59 and then locked in adjusted position by a lock nut 66. By this adjustment the location of the valve 42 with respect to its seat can be determined when the thermostat is cold wit-h its head 56 contracted againstthe stop 57.

The bore of the sleeve 59 also constitutes end and received within the socket 68 pro vided by an elongated annular boss 69 on the movable end wall 56 of the thermostat 53. The opposite end of the rod 67 is provided with a knife edge or pointed and is received within a notch in a rocker 70 which is fulcrumed b means of knife edges 71 upon a bracket 7 2 extending upwardly from 'a plate 7 3. Plate 73 is preferably provided with an aperture and fits over the upwardly projecting end of the sleeve 59 so that it may be rotated around said. upwardly projecting end for purposes of adjusment to the end that the connections from the stem 67 to the valve stem 46 may be properly tutes with said rocker 70 a lever fulcrumed at 71 for transmitting movement from the thermostat stem 67 to the valve stem 46. said bar or rod 51 is preferably provided on the thermostat side of the fulcrum 71 with one or more slidably mounted weights 77 which may be retained in adjusted position in any suitable way as by set screws 78. Said weights are preferably so shaped that the center of gravity of the lever with 1tsweights is above the plane of the fulcrum 71 so that the'movement of the lever is accompanied by a shift of the center of gravity in the same direction as the thermostat tends to move the valve. This arrangement possesses the advantage that the change in position of the center of gravity tends to compensate for the change in resistance to expansion of the thermostat 53 offered by the resiliency of its lateral wall. 54. The dispositon of said weight 77 on the opposite side of the stem 67 from the fulcrum 71 causes said weights to maintain the knife edges of said fulcrum in operative position, because tending to tilt the rocker aligned. This fulcrum member 72, 73 may I about the upper end of the stem 67 as an axis. The opposite end of the bar or lever 51 is preferably provided with a lighter weight 79 which may be moved longitudinally of the bar or rod 51 to nicely predetermine the temperature at which the thermostat 53 starts to open the valve 42. To retain weight 79 in its adjusted position the upper surface of the bar or rod 51 is preferably serrated as shown at and the slot through said weight 79 may be provided with a tooth for engagement in the serrations 80.

This manner of mounting the thermostat and its operating connections to the valve member provides for ready adjustments that can be easily made by unskilled persons. The fulcrum member 72, 73 may be readily brought into line so that the bar or rod 51 will extend at right angles from its fulcrum to the point of attachment of the valve stem 46, and may be fixedly clamped in its adjusted position by the lock nut 7t or other suitable head on the sleeve 59. During such adjustments the fulcrum member, rotating around the tube 59, moves about the axis of the connections from the thermostat to the lever and, owing to the point contact between the stem 67 and the thermostat wall 56, such adjustments may be effected with-v out disturbing said connections. Similarly the thermostat 53 may be rotatably and axially adjusted by threading the support 63 on to or off of the inwardly projecting end of the sleeve 59, and then be fixedly clamped in adjusted position by the lock nut 66. During such adjustments the thermostat is also moving about the axis of the connections therefrom to the lever 70, 51 and owing to the point of contact between the stem 67 and the thermostat wall 56 these adjustments may be effected without rotating or otherwise disturbing said connections. At the same time the connections between the thermostat and the lever are securely held against accidental displacements owing to the length of engagement between the stem 67 and the wall of the socket 68. The form of the connection of the bar or rod 51 to the valve member 42 is such that the valve stem 46 need not extend exactly in the axis .of the valve port, the spherical surface of engagement of the valve member with the valve seat permitting considerable variation in the contact of the member with its seat without danger of leakage and the free passage of the valve stem through the aperture 49 insuring against the sticking of said stem if the latter be somewhat out of alignment. Moreover, the connections between the thermostat and the valve and their manner of mounting are such that substantially no frictional opposition to movement exists, while the character of these connections is such as to facilitate expansion and contraction of the thermostat and therefore a nicer and more accurate control of the valve. At the sametime the weights provide an adjustment whereby the temperature at which the thermostat will respond to operate the valve may be nicely regulated within very close limits.

It will therefore be perceived that an incubator has been provided with thermostatic mechanism whereby the temperature of the water is closely and accurately maintained at a predetermined temperature and the extent of circulation of this water of predetermined temperature is accurately and closely regulated from the temperature of the air within the incubator casing. At the same time the provisions for adjustment to maintain this nicely regulated temperature are simple and easily manipulated so that necessary adjustments may be readily effected by unskilled persons. The entire structure is also free of complexities so that it may be readily assembled and installed by unskilled persons, while the character of its component parts is such as to facilitate economical manufacture and operation.

While the embodiment of the invention illustrated on the drawings has been described with considerable particularity, it is to be expressly understood that the invention is not restricted thereto as the same is capable of receiving a variety of mechanical expressions, some of. which will now readily suggest themselves to those skilled in the art, while changes may be made in the details of construction, arrangement and proportion of parts, and certain features used} without other features, without departing from the spirit of this invention. Reference is therefore to be had to the appended claims for a definition of the limits of the invention.

What I claim is 1. In an incubator, in combination with the incubator casing, means for regulating the temperature within said casing including a valve and a lever for operating the same, a sleeve projecting through the casing wall, an adjustable fulcrum plate for said lever clamped in position by said sleeve, a thermostat adjustably mounted on the inner end of said sleeve, and a rod projecting freely through said sleeve and'contacting the movable wall of said thermostat and said lever. 2. In an incubator, in combination with the incubator casing, means for regulating the temperaturewithin said casing including a valve and a lever for operating the same, a sleeve projecting through the casing wall, a thermostat rotatably adjustable about the axis of said sleeve, a fulcrum plate for said lever rotatably adjustable about the axis of said sleeve, and an operative connection having contact engagement with said thermostat and said lever extending in the axis of said sleeve.

3. In an incubator, in combination with the incubator casing, means for circulating water through said casing, a valve and a thermostat subjected to the temperature within said casing for controlling the circulation of water, a heater for said water outside of said casing including an upwardly extending flue for the passage of hot air without contact with the heating surface and reverse'flues adjacent .the heating surface communicating with said firstnamed flue, a valve for determining whether or not the hot air shall traverse said reverse fiues, and a thermostat subjected to the temperature ofthe water for operating said last-named valve.

4. In an incubator, in combination with the incubator casing, means for regulating the temperature within said casing including a water circulation system, a valve in saidsystem and a lever for operating the same, a sleeve projecting through said casing, a thermostat adjustably mounted on the inner end thereof, a member operatively connecting said thermostat and lever passing through said sleeve, an adjustable fulcrum member for said lever clamped in adjusted position by said sleeve, a second thermostat in said circulating system, a heater for said water, and controlling means therefor having .operative connection with said second thermostat.

5. In an incubator, in combination with the incubator casing, a system for circulating water therethrough,,means for regulating the flow of said water including a valve in said system, said valve including a spherical portion for engagement with the valve seat and a conical extension projecting through the valve port, a lever for operating said valve, a sleeve projecting through said casing, a thermostat adjustably mounted on the inner end thereof having operative connections with said lever passing through said sleeve, an adjustable fulcrum member for said lever clamped in adjusted position bysaid sleeve, a heater for said water, controlling means therefor, and

a second thermostat located in said circulating system operatively connected to said controlling means.

6. In an incubator, in combination with an incubator casing, a system for circulating water therethrough, a heater for said water, controlling means therefor, a thermostat in said system operatively connected to said controlling means, and means for regulating the temperature within said. casing including a valve in said system, a valve stem therefor, a lever engaging said valve stem, a fulcrum for said lever, an adjustable weight on said lever between said fulcrum and valve stem, a sleeve projecting through said casing, a thermostat mounted thereon within said casing, a member operatively connecting said thermostat and lever passing through said sleeve, and one or more adjustable weights on said lever on the opposite side of said fulcrum from said valve stem and so ositioned that the center of gravity of said lever and weights is above said fulcrum.

.7. In an incubator, in combination with the incubator casing, means for regulating the temperature within said casing including a valve and a lever for operating the same, a sleeve projecting through the casing wall, means clam ing said sleeve to said wall, an adjustable ulcrum plate for said lever clamped in osition by said sleeve, a thermostat adjusta ly mounted on the inner end of said sleeve, and a rod projecting freely through said sleeve and contacting the movable wall of said thermostat and said lever.

8. In an incubator, a circulating system, a valve controlling the flow of heating medium therethrough, a lever for operating said valve, a thermostat within said incubator and operatively connected to said lever, said lever carrying one or more adjustable weights so positioned that the center of gravity of said lever and weights is above said fulcrum.

In testimony whereof I have signed this specification.

JEAN v. GIESLER.

Images