23,914. British Thomson-Houston Co., [General Electric Co.]. Oct. 30. Switches.-A contact-arm operated by an electromagnet is arranged in parallel with the resistance arm of the controller so that the circuit is broken at its contacts. The circuit of the electro-magnet is completed by the initial movement of the resistance arm, or by auxiliary switches used for jogging the motor. The device may be employed to control motors driving printing - presses. A double-acting spring 16 tends to hold the controller arm 14 in the position shown, in which the brushes 20, 21, 22, 23 carried by the arm are in engagement with connecting portions of the segments 17 &c. When the arm 14 is moved in either direction, the brushes 20, 21, 23 pass on to insulating-portions 26, 27, 28 before passing on to the conducting-parts. The arm 14 also carries a brush 24, which makes contact with a stud 25 before the arm starts to cut out resistance. The core of the electro - magnetic switch 29 carries bridging-contacts 30, 31, and the latter normally closes the circuit of the no-volt coil 32. The running speed of the motor is controlled by a resistance 34 connected preferably in the shunt field circuit. The arm 35 may be placed in any position on this resistance and held by a latch 37. A key 40 is required to release the detent 39 to enable the switch arm 35 to be set. When the parts are in the positions shown, the motor can be jogged by closing one of the switches 33 and energizing the electro-magnet 29. The motor circuit is then completed from the positive main, through the series field SF, conductor 41, resistance 12, contact 30, segment 17, conductor 42, armature A, contact 19, and brushes 23, 22, to the negative main, and the resistance R is connected across the brushes. The motor then runs at a low speed, and may be brought up to normal speed by moving the arm 14. The initial movement of the arm 14 may be used, instead of one of the switches 33, to energize the solenoid 29. The circuit is completed from the positive main, through solenoid 29, conductor 43, brushes 24, 22, and segment 18, to the negative main. On further movement of the arm 14, the brush 20 cuts out the resistance 12, and the brushes 20, 21 are in parallel with the bridging- contact 30. The brush 24 passes off the contact 25, and the electro-magnet 29 is de-energized so that its core drops, thus closing the circuit of the no-volt coil 32 across the contact 31. The motor can be stopped by closing one of the switches 33 to open the circuit of the coil 32. The arm 14 returns to its 'off' position, and by opening the switch 33 employed the motor circuit is broken at the contact 30. Or, if the switch 33 is opened quickly, the circuit of the electro-magnet 29 will be completed across the contacts 24, 25 as the arm 14 returns. This raises the contact 30 and again lets it drop to break the circuit. Specification No. 2629, A.D. 1906, is referred to.