Electrical Supply Company, Chicago, Illinois

Electrical Novelties.

The accompanying cuts illustrate several novelties recently put on the market by the Electrical Supply company, of Chicago. Fig. 1 shows the Turnquist door spring. Many springs have been designed for the closing of the electrical circuit when the door is opened, but nearly all have serious objections. A large part of the door jamb has to be removed, or a large aperture made to contain the working parts. The springs have within themselves an insulating medium, which is liable to shrink and deteriorate, permitting constant leakage and false alarms. The Turnquist spring has no insulating substance entering into its make-up, and requires but the boring of a half-inch hole in the door jamb for its insertion. The contact is separated by a slight distance, the jamb itself performing the function of insulation. A sliding contact is obtained, which is very valuable for keeping the surface bright.

Fig. 1. Turnquist Door Spring.

Fig. 2 shows the latest construction of the automatic ground switch. A full description of the old form of this switch has been given in the WESTERN ELECTRICIAN, but the construction has been changed. One of the switch arms has been extended for the fastening of the handle. The automatic releasing device will cause the switch to operate when a ground occurs which would be sufficient to jeopardize life or property. A slight or extremely high resistance ground will not operate the switch. It is, therefore, not unduly sensitive, and will not. operate without sufficient cause. It can be operated as an ordinary double-pole hand switch by the pushing of a button which projects slightly from the lower part of the switch. Its action is instantaneous, and throughout is well designed.

Fig. 2. Automatic Ground Switch.

The new lava insulators are illustrated in Figs. 3 and 4. The application and utilization of lava as an insulator have been growing for the past two years. Electrical manufacturers have not been slow in adopting an insulator which is perfectly non-combustible, and at the same time is almost entirely free from changes due to moisture.

Fig. 3. Lava Insulators. Fig.4.

Fig. 5 illustrates the Electrical Supply company's new medical faradic coil. It is durably constructed, neat in appearance, and perfect in operation. While in action the power of the current is under perfect control. Cords and terminals are furnished, forming a part of the outfit, by means of which the electrodes can be taken at some distance from the apparatus. The proportions have been worked down with great care, so that with a given battery strength the greatest faradic effects are produced.

Fig. 5. Medical Coil.