Speed Indicator Warns Driver by Flashing Red Light (Oct, 1938)

Speed Indicator Warns Driver by Flashing Red Light
When the automobile exceeds a predetermined speed, a new indicator flashes a red light to warn the driver. The indicator, made in the form of a devil’s head, is red. Inside it is a light which is turned on when electrical contact is established by a metal disk actuated by air current from the automobile’s fan. The air current fluctuates in relation to the motor speed. Tension of the disk may be adjusted by means of a regulator on the dash. The indicator is small and may be hooked to the fabric in the top of the car, at the driver’s left.

  1. Don says: December 13, 20079:09 am


  2. Splognosticus says: December 13, 20079:26 am

    Filed under Aviation? How fast are these guys going, anyway?

  3. Alan J. Richer says: December 13, 20079:58 am

    Not going to work all that well – the fan speed will blow this thing into a false reading in lower gears. Nice try, though…8)

  4. Charlie says: December 13, 200710:26 am

    Whoops, fixed the category. Thanks splog.

  5. nlpnt says: December 14, 20079:51 am

    Why did they give it its’ own sender instead of working off the existing speedometer drive cable?

  6. Firebrand38 says: December 14, 20072:13 pm

    I think rather than automobile speed this was more of a makeshift tachometer for a 1938 car. They’re talking about speed in rpm’s and not in mph.

    A possible clue may be found in the drawing of the driver’s hands. Those appear to be feminine gloves with the implication that this device was to keep “m’lady” from over revving a car with a standard transmission. That’s my assumption.

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