318 



CENTRAL, SCIENTIFIC CO., CHICAGO, U. S. A. 



7S90. 

 7891. 



DeKhotinsky Bimetallic Therms 



Regulator. 

 (Patent Applied for.) 



INCUBATORS, ELECTRICALLY HEATED AND REGULATED 



INCUBATORS, Triple Wall, DeKhotinsky Electrically Heated and Regulated (Patented), with 

 new bimetallic regulator and new system of ventilation providing for greatest possible uni- 

 formity of temperature throughout the incubator chamber. 



Construction: These incubators are constructed of asbestos board on a steel frame, with three 

 walls. The space between the two outer walls is packed with magnesia-asbestos (magnesia 

 85 per cent; asbestos 15 per cent). Between the inner walls is an air space, through which 

 the air passes upward from the heating units in the base. Ports are provided in the inside 

 walls of this air space, permitting the entrance of the heated air to the incubator chamber, 

 in which it passes up and out through an opening in the false top. The location of these ports 

 has been carefully and scientifically determined so as to provide a continuous current of 

 heated air to every corner of the inner chamber making the temperature uniform throughout. 

 This feature (patent pending) is peculiar to the DeKhotinsky Triple Wall Incubator, and in- 

 sures a uniformity not possible in electrically heated incubators of any other type. The outer 

 door is double walled and packed with magnesia-asbestos. It is beveled on the edges, making 

 close contact, when closed, with the walls, thus preventing leakage of heat. An inner glass 

 door is provided for inspection of the interior without cooling the contents. Between it and 

 the outer door is a dead air space for insulation purposes. 



Heating of the incubator is effected by means of four of our standard heating units of Chromel 

 wire wound on lavite. Those heating units are located in the base of the incubator between 

 the two bottoms, with an iron deflector placed over, them to prevent radiation of heat from 

 the units into the inner chamber. Three of these heating units are connected in parallel to the 

 switch contact springs, and may be added to the circuit one at a time as desired. The fourth 

 is connected in circuit with the contact points of the thermo-regulator. These heating units 

 can be easily and quickly replaced from outside the incubator without the necessity of open- 

 ing the door or stopping the operation. 



Temperature control of the incubator is secured by means of our new bimetallic thermo-regula- 

 tor which is made from invar-brass ribbon, and can be set at any desired temperature from 

 that of the surrounding air up to the maximum heat capacity of the incubator. This range 

 of temperature permits the use of these instruments as incubators, paraffine baths, drying 

 ovens or sterilizers. The precision of action of this thermo-regulator is ^"G. The make-and- 

 bteak contact of the thermo-regulator is located outside the incubator, to prevent the possi- 

 bility of ignition of inflammable gases, developed in the inner chamber when used as a dry- 

 ing oven, which often occurs when the contact is made and broken inside. A pilot lamp on 

 top of the incubator is connected in series with the thermo-regulator, enabling the operator 

 to determine at a glance whether the incubator is regulating. These instruments can be oper- 

 ated on either A.C. or D.C. circuits. Complete with Hubbell receptacle and five feet of flex- 

 ible asbestos covered cord with separable Hubbell attachment plug. 



No A B C 



Height inside, inches 10% 14% 19% 



Width inside, inches 17 



Depth inside, inches 6% 11% 14 



Shelf space, square inches 91 282 47f> 



For 110 volts $55.00 90.00 145.00 



For 220 volts 57.50 92.50 147.50 



T.,r EXTRA HEATING UNITS for Nos. 7830-1, see Nos. 7520-7. 



