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US 4,253,690 AGranted
Safety knob
OwnerNathan Hollanderinventor
Life of this patent
Estimating the term…
Abstract
A safety knob for preventing unauthorized persons, such as small children, from operating the knobs in a given direction; but enabling even the unauthorized persons to operate the knob in the opposite direction.
Claims12
An improved safety knob for use in operating a stem,
- said safety knob comprising:
- outer knob means;
- first means for normally coupling said outer knob to said stem only when said outer knob is moved in a first direction to cause said stem to move with said outer knob;
- second means having normal and operated positions,
- said second means in said operated position coupling said outer knob to said stem regardless of the direction moved of said outer knob;
- and
- said outer knob means being operatively coupled to the stem only through said first means, when said second means is in the normal position.
4 more elements
An improved safety knob for use in operating a stem,
- inner knob means attached to the stem,
- outer knob means,
- first means for normally coupling said outer knob to said inner knob only when said outer knob is moved in a first direction to cause the inner knob to move with said outer knob and thereby move said stem in said first direction, and
- said second means for coupling said outer knob to said inner knob regardless of the direction of movement of said outer knob.
1 more element
An improved safety knob for use in rotating a stem,
- said safety knob comprising handle means,
- means for attaching said handle means to the stem,
- means for preventing unauthorized persons from turning the knob means in a first direction to cause said stem to rotate in said first direction,
- said last named means comprising control means associated with said knob means for causing said stem to rotate with said knob responsive to the operation of said control means,
- the improvement characterized in this that means are provided for turning said stem a second direction through the operation of said knob in said second direction means even with said control means in the non-operated condition.
2 more elements
Dependencies are inferred from the claim text.