US1797885A - Electromagnetic driving direction indicator - Google Patents

Description

March 24, 1931' v F E A 1,797,885

ELECTROMAGNETIC DRIVING DIRECTION INDICATOR Filed March 14. 1929 Patented Mar. 24, 193T UNITED. STATES PATENT OFFICE ELECTROMAGNETIC DRIVING DIRECTION INDICATOR Application filed limb 14, 1929, Serial No.

Electro-magnetic driving direction indicators can be divided into two main types, that is, the so-called drum indicators in which a disc is rotated by means of an electro- 6 magnetic yoke, so that the driving direction may be indicated by the position of said disc; and the so-called Winkers angle arm indicators in which an indicator arm is moved by the electro-magnet from its normal vertical 10 position into an upright indicating position.

The last mentioned type ofindlcator possesses the advantage that whenthe angle arm is in the indicating position the contour of the instrument is altered, so that it is 1 more clearly visible, and consequently complies with many oflicial regulations for public trafiic vehicles that only such indicators are to be'used.

The resent invention relates to such an angle indicator. In the hitherto known forms of construction there is always a firm connection, arranged directly or indirectly, between the angle arm and the magnet core actuated by the solenoid. As however in-order to, avoid having a dead point, the axis of the point of attachment cannot lie in a vertical plane with the axis of rotation of the angle arm, but must be shifted a little to one side, the magnet core describing a double curve.

lating coil, or one of special construction. The first mentioned form of construction takes up a comparatively large amount of room, and also necessitates movable wire con nections, whilst the last mentioned form is comparatively expensive in construction. Furthermore all these movable connections and arrangements are uncertain in action, as by inappreciable alterations in the shape, or 40 by the collection of dirt thereon, resistances are created, which the battery, always giving only a small current, is unable to. overcome.

A further defect of these angle arms consists in the fact that they are easily moved out of the normal vertical osition by the vi bration of the vehicle and cation. This defect can only be remedied by springs or control magnets in a complicated This necessltates the use of an 0scil-- in this way' also give rise to uncertain action or faulty 1nd1- indicator comprising a pivoted indicator arm 346,912, and in Germany March 2a, 1928.

manner and even then the defect could not be surmounted with certainty. I

The present invention overcomes all these defects, whilst at the same time simplifying the construction of the part controlling the angle arm. The main characteristic of the invention consists in that. the actuating slot through which the magnet core engages the angle arm, is provided with a cut-out part which rests on the actuating pin ofthe arm in the normal position of the angle arm, so that the weight of the magnet' core holds the angle arm in the normal position, and in the simplest possible manner.

The accompanying drawing shows as an example a form of construction of such an arrangement in a driving direction indicator in Fig. 1 in the normal position and in Fig. 2 in the working position.

The angle arm top a is provided with a simple or hook shaped stud, or so-called carryingpin 6, whose curving movement is taken up by the slot 0 of the-free magnet core (1 freely moving without any point of attachment in the magnet coil 8. A cut-out part 2' sur- 5 rounds the pin 7; of the indicator arm at its drop into the normal position, and retains it in this position until current is switched on and raises the magnet core up from the pin. In orderrto reduce friction a friction roller can be fitted on the pin b. Thecasing -g surrounds the arrangement.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. -An electromagnetic driving direction indicator comprising a movable pivoted indicator arm having a projection offset from'the pivot, a core arranged above said arm and 7. having an open slot to receive said projec- .tion, said core fitting snugly in the coil of a solenoid the upper wall of said slot comprising a seat adapted to cooperate with said pro 5- jection and to support the core upon said proectlon, whereby to maintain the arm in its downward position by the weight of the core. 2. In an electromagnetic driving direction having a projecting pin in proximity to and spaced from the point where the arm is pivoted, a core arranged above said arm and having a slot receivin said pin, said core fittin snugly in the coil of a solenoid, and a seat defining part of the slot adapted to cooperate with the pin and support the core upon the pin, whereby to maintain the arm in one position by the weight of the core.

In testimony that I claim the foregoing as my invention, I have signed my name hereto.

FRIEDRICH KARL TEICHGRBER.

Images