Positive-positioning knob assembly

A positive-positioning knob assembly comprising:

• a knob body having a hollow, open-ended substantially cylindrical interior;
• a pinion member fixed against rotation;
• cap means non-rotatably mountable to said body and to said shaft for providing a top closure for the former and for rotating said shaft in response to rotation of said body and cap relative to said pinion member;
• cooperating, selectively interengageable and disengageable locking means on said pinion member and said body respectively for alternatively permitting said body and shaft to rotate freely of said pinion member when said locking means are in a disengaged condition, and for locking said body and shaft non-rotatably relative to said pinion when said locking means are in an engaged condition;
• and resilient biasing means for normally holding said locking means in said engaged condition to prevent rotation of said shaft by said knob body and cap, and resiliently deformable for permitting said locking means to move to said disengaged condition for permitting rotation of said shaft by said body and cap;
• wherein said locking means comprises a plurality of circumferentially spaced, radially outwardly projecting teeth on said pinion member and at least one complementary, radially inwardly projecting tooth on said hollow interior of said body, and wherein said resilient biasing means comprises a compression spring engaged between said pinion member and said cap for normally holding the teeth of said body in engagement with the teeth of said pinion, and resiliently compressible for permitting the teeth of said body to disengage the teeth of said pinion to permit rotation of said body and cap relative to said pinion and hence permit rotation of said shaft thereby;
• and wherein said pinion includes a downwardly extending, generally cylindrical skirt portion having an outer diameter smaller than an inner diameter defined by the teeth thereof and of sufficient axial height to receive said body teeth freely rotatable thereabout when said body and said cap are depressed to overcome said compression spring and disengage the respective teeth.

A positive-positioning knob assembly comprising:

• a knob body having a hollow, open-ended substantially cylindrical interior;
• a pinion member fixed against rotation;
• cap means non-rotatably mountable to said body and to said shaft for providing a top closure for the former and for rotating said shaft in response to rotation of said body and cap relative to said pinion member;
• cooperating, selectively interengageable and disengageable locking means on said pinion member and said body respectively for alternatively permitting said body and shaft to rotate freely of said pinion member when said locking means are in a disengaged condition, and for locking said body and shaft non-rotatably relative to said pinion when said locking means are in an engaged condition;
• and resilient biasing means for normally holding said locking means in said engaged condition to prevent rotation of said shaft by said knob body and cap, and resiliently deformable for permitting said locking means to move to said disengaged condition for permitting rotation of said shaft by said body and cap;
• wherein said cap has a radially inner depending skirt for non-rotatable engagement with said shaft and a resiliently deformable, generally oval radially outer depending skirt portion having a maximum transverse dimension greater than an inner diameter of said body hollow interior for interfitting therewith in a friction fit.

A positive-positioning knob assembly comprising:

• a knob body having a hollow, open-ended substantially cylindrical interior;
• a pinion member fixed against rotation;
• cap means non-rotatably mountable to said body and to said shaft for providing a top closure for the former and for rotating said shaft in response to rotation of said body and cap relative to said pinion member;
• cooperating, selectively interengageable and disengageable locking means on said pinion member and said body respectively for alternatively permitting said body and shaft to rotate freely of said pinion member when said locking means are in a disengaged condition, and for locking said body and shaft non-rotatably relative to said pinion when said locking means are in an engaged condition;
• and resilient biasing means for normally holding said locking means in said engaged condition to prevent rotation of said shaft by said knob body and cap, and resiliently deformable for permitting said locking means to move to said disengaged condition for permitting rotation of said shaft by said body and cap;
• wherein said locking means comprises a plurality of circumferentially spaced, radially outwardly projecting teeth on said pinion member and at least one complementary, radially inwardly projecting tooth on said hollow interior of said body, and wherein said resilient biasing means comprises a compression spring engaged between said pinion member and said cap for normally holding the teeth of said body in engagement with the teeth of said pinion and resiliently compressible for permitting the teeth of said body to disengage the teeth of said pinion to permit rotation of said body and cap relative to said pinion and hence permit rotation of said shaft thereby;
• and wherein said compression spring abuts an undersurface of said cap and a surface of said pinion facing said under-surface of said cap.

A positive-positioning knob assembly comprising:

• a knob body having a substantially hollow interior portion;
• a pinion member fixed against rotation;
• cooperating, selectively interengageable and disengageable locking means on said pinion member and said hollow body interior respectively for alternatively permitting said body to rotate freely of said pinion member when said locking means are in a disengaged condition, and for locking said body non-rotatably relative to said pinion when said locking means are in an engaged condition;
• and resilient biasing means for normally holding said locking means in said engaged condition to prevent rotation of said knob body;
• said resilient biasing means being resiliently deformable for permitting said locking means to move to said disengaged condition for permitting rotation of said knob body;
• and further including a cap which has a radially inner depending skirt for non-rotatable engagement with said shaft and a resiliently deformable, generally oval radially outer depending skirt portion having a maximum transverse dimension greater than an inner diameter of said base hollow interior for interfitting therewith in a friction fit.