US 4,757,598 AGranted

Two speed transmission for power driven threading machine

AssigneeEmerson Electric Co.

InventorJames C. Redman

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Abstract

A transmission is disclosed for rotating the work supporting chuck assembly of a power driven threading machine at low and high speeds. The transmission includes a sun gear, a ring gear coaxial with the sun gear and axially shiftable between first and second positions relative to the sun gear and to a fixed clutch component, and a plurality of planet gears between the sun gear and ring gear. The sun gear is motor driven to provide the transmission input, and the planet gears are connected to and drive an output sprocket wheel drivingly connected to the chuck assembly. The first position of the ring gear provides clutched interengagement thereof with the sun gear for rotation therewith, whereby the planet gears rotate therewith to rotate the output sprocket wheel at a first speed equal to the speed of rotation of the sun gear. The second position of the ring gear provides for clutched engagement thereof with the fixed clutch component such that the sun gear rotates the planet gears relative to the ring gear, whereby the output sprocket wheel is driven at a second speed which is less than the speed of rotation of the sun gear. The ring gear is axially shifted between its first and second positions through a yoke mechanism which includes high speed and low speed springs by which the clutched engagement of the ring gear with the sun gear is achieved with a first biasing force and the clutched engagement between the ring gear and fixed clutch component is achieved with a second biasing force which is greater than the first force.

Claims27

Dependent claims

A power driven threading machine comprising, base means, rotatable chuck means having an axis and axially opposite ends, jaw means at said opposite ends of said chuck means for gripping a workpiece, said chuck means being supported on said base means for rotation about said chuck axis, and means including transmission means for driving said chuck means in a threading direction about said chuck axis and selectively at two different speeds, said transmission means having an axis and including input means, output means and planetary gear means therebetween, said planetary gear means including sun gear means coaxial with said transmission axis and connected to one of said input and output means, ring gear means coaxial with said sun gear means, and planet gear means coaxial with said sun gear means, said planet gear means being radially between said sun gear means and said ring gear means and connected to the other of said input and output means, said ring gear means being axially shiftable relative to said sun gear means and planet gear means between first and second positions, first clutch means interengaging said ring gear means and sun gear means in said first position of said ring gear means for rotation together, whereby said planet gear means rotate therewith and said output means is driven at a first speed, second clutch means engaging said ring gear means in said second position thereof against rotation with said sun gear means whereby said planet gear means rotates relative to said sun gear means and said ring gear means and said output means is driven at a second speed different from said first speed, means connecting said output means to said chuck means, and means to selectively shift said ring gear means between said first and second positions.

A power driven threading machine comprising, base means, rotatable chuck means having an axis and axially opposite ends, jaw means at said opposite ends of said chuck means for gripping a workpiece, said chuck means being supported on said base means for rotation about said chuck axis, and means including transmission means for driving said chuck means in a threading direction about said chuck axis and selectively at two different speeds, said transmission means having an axis and including sun gear means, ring gear means and planet gear means coaxial with said transmission axis, said planet gear means being radially between said sun gear means and said ring means, means for driving said sun gear means at a first speed, said ring gear means being axially shiftable relative to said sun gear means and planet gear means between first and second positions, said ring gear means having first surface means and said sun gear means having clutch surface means frictionally engaging with said first surface means when said ring gear means is in said first position, whereby said sun gear means, ring gear means and planet gear means rotate together at said first speed, clutch member means coaxial with said ring gear means and fixed against rotation about said transmission axis, said ring gear means having second surface means and said clutch member means having clutch surface means frictionally engaging with said second surface means when said ring gear means is in said second position, whereby said ring gear means is engaged against rotation with said sun gear means and said planet gear means rotates relative to said sun gear means and ring gear means at a second speed less than said first speed, means for drivably connecting said planet gear means to said chuck means, and means for selectively shifting said ring gear means between said first and second positions thereof.

Dependencies are inferred from the claim text.