Motor speed sensor
OwnerCharles Elbert Robinsoninventor
Life of this patent
Estimating the term…
Abstract
A motor speed sensor for sensing the RPM speed of a motor is designed to be placed in line with a conventional mechanical tachometer take-off. The motor speed sensor includes rotatable shafts interconnecting the mechanical tachometer take-off so that the mechanical delivery to the tachometer is preserved and further includes a notched interrupter which rotates in cooperation with the interconnecting shafts. The notches of the interrupter are disposed to rotate between a photo-electric detector and a light source thereby interrupting the beam of light in order to provide a stream of output pulses whose frequency is directly proportional to the speed of the motor.
Claims10
A motor speed sensor for placement between a take-off from said motor and a flexible drive for a tachometer, said take-off providing rotation proportional to the speed of said motor, said sensor comprising:
- means connected to said take-off for extending the rotation of said take-off to said flexible drive,
- a light source for providing a beam of light,
- means operative with the rotation of said extending means for interrupting the beam of light at a rate that is proportional to said speed of said motor, and
- means receptive of said interrupted beam for generating a series of pulses, the frequency of said pulses being proportional to said speed.
A motor speed sensor for placement between a take-off from said motor and a flexible mechanical drive for a tachometer, said take-off providing rotation proportional to the speed of said motor, said sensor comprising:
- a shaft, said shaft by having one end coupled to said take-off being capable of rotating in sync with said take-off,
- a rod, said rod by having one end coupled to the remaining end of said shaft being capable of rotating in sync with said shaft,
- means connected to the remaining end of said rod for coupling to said flexible drive,
- a light source for providing a beam of light,
- means operative with the rotation of said rod for interrupting the beam of light at a rate that is proportional to said speed of said motor, and
- means receptive of said interrupted beam for generating a series of pulses, the frequency of said pulses being proportional to said speed.
A motor speed sensor for placement between a take-off from said motor and a flexible mechanical drive for a tachometer, said take-off providing rotation proportional to the speed of said motor, said sensor comprising:
- a shaft, said shaft by having one end coupled to said take-off being capable of rotating in sync with said take-off,
- a rod, said rod having one end coupled to the remaining end of said shaft being capable of rotating in sync with said shaft,
- means connected to the remaining end of said rod for coupling to said flexible drive,
- a light source for providing a beam of light,
- means operative with the rotation of said rod for interrupting the beam of light at a rate that is proportional to said speed of said motor,
- means receptive of said interrupted beam for generating a series of pulses, the frequency of said pulses being proportional to said speed,
- means enclosing said shaft and said rod, said enclosing means being capable of preventing dust from around said shaft and said rod,
- said flexible drive having formed at said end coupled to said rod a passageway having a downwardly protruding keyway and said rod at said end coupled to said drive having a diameter substantially corresponding to the diameter of said drive passageway and further having a key protruding downwardly to mate with said drive keyway, said rod being supported in enclosing means by means of a washer disposed near said coupling of said rod to said flexible drive, and
- said enclosing means comprising a first plurality of bearing surfaces operative upon said rod for rigidly supporting said rod in alignment with said shaft and a second plurality of bearing surfaces operative upon said shaft for rigidly supporting said shaft in alignment with said rod and with said take-off.
Dependencies are inferred from the claim text.