Fly press

Claim 2

A fly press, which comprises a frame, a nut carried by said frame, a press screw having two oppositely handed screw threads near opposite ends, one of said screw threads being in threaded engagement with said nut, a press ram which is in threaded engagement with the other of said screw threads, axially movable relative to said frame and held against rotation relative thereto, a flywheel mounted on said press screw for rotation therewith, and drive means for reciprocating said ram.

Claim 3

A fly press as set forth in claim 1, in which said drive means comprise double-acting piston-cylinder units.

Claim 4

A fly press as set forth in claim 2, in which said press screw is rotatably mounted in and axially fixed to a bridge member disposed between said screw threads, said frame comprises a traverse, and said piston-cylinder units are connected at one end to said traverse and at the other end to said bridge member, whereby said press ram is arranged to reciprocate at a speed which is higher than that at which said piston-cylinder units are operated.

Claim 5

A fly press as set forth in claim 3, in which said piston-cylinder units extend through said traverse.

Claim 6

A fly press as set forth in claim 2, in which said flywheel is mounted on said screw above both said screw threads, said press screw is rotatably mounted in and axially fixed to a bridge member disposed over said flywheel, said frame comprises a traverse, and said piston-cylinder units are connected at one end to said traverse and at the other end to said bridge member, whereby said press ram is arranged to reciprocate at a speed which is higher than that at which said piston-cylinder units are operated.

Claim 7

A fly press as set forth in claim 1, in which said nut is rigid with said frame.

Claim 8

A fly press as set forth in claim 1, which comprises a second nut carried by said frame, a second press screw having two oppositely handed screw threads near opposite ends, one of said screw threads of said second press screw being in threaded engagement with said second nut, said press ram being in threaded engagement with the other of said screw threads of said second press screw, and a second flywheel mounted on said second press screw for rotation therewith, said screw threads and nuts being designed to impart a rotation in opposite senses to said two press screws in response to an axial movement of said ram, whereby said flywheels exert mutually balancing torques on said frame.

Claim 9

A fly press as set forth in claim 7, in which said nuts are rigid with said frame, said press screws are axially movable relative to said frame, said flywheels are axially fixed to said press screws, said frame carries two annular stops, which are engageable by said flywheels to limit the axial movement of said press screws, said annular stops are screw-threadedly engaged with said frame to permit of an adjustment of said stops, and a gear is interposed between and in driving connection with said stops to enable a simultaneous adjustment of said stops by an operation of said gear.

Claim 10

A fly press as set forth in claim 1, in which said nut is rigid with said frame, said press screw is axially movable relative to said frame, said flywheel is axially fixed to said press screw, said frame carries an annular stop which is engageable by said flywheel to limit the axial movement of said press screw, and said annular stop is screw-threadedly engaged with said frame to permit of an adjustment of said stop.

Claim 11

A fly press as set forth in claim 1, which comprises nut-mounting means carried by said frame and mounting said nut so that the same is axially movable relative to said frame and held against rotation relative thereto.

Claim 12

A fly press as set forth in claim 10, in which said nut is engageable with said frame to limit tHe movement of said ram.

Claim 13

A fly press as set forth in claim 1, in which said screw carries a flange, which is engageable with said nut to limit the movement of said ram.

Claim 14

A fly press as set forth in claim 12, in which said screw consists of two axially aligned parts, which are connected by said flange.