초록 ▼

The system for rotating the transfer plate of a coating system in a vacuum chamber consists of a transfer plate driver assembly on the outside of the chamber at the axis and a transfer plate rotator assembly inside the chamber. The driver assembly consists of a pneumatic actuator for linear motion,

The system for rotating the transfer plate of a coating system in a vacuum chamber consists of a transfer plate driver assembly on the outside of the chamber at the axis and a transfer plate rotator assembly inside the chamber. The driver assembly consists of a pneumatic actuator for linear motion, a barrel cam which translates the linear motion into rotary motion with high torque at starting and stopping positions, and a rotary feedthrough all in a structural housing. The rotator assembly comprises a central hub with means for supporting the end walls, a transfer plate hub assembly and a ratchet arm connected to the rotary feedthrough. As the pressure plate assembly is drawn back by the ram, it in turn draws back the transfer plate and engages the ratchet arm with the transfer plate hub. The actuator then rotates the transfer plate. The ram then reverses direction, the ratchet arm disengages and is returned to its initial position.

대표청구항 ▼

1. An apparatus for rotating a transfer plate inside a cylindrical vacuum chamber having front and back end walls and for translating a pressure plate, comprising: a central hub attached to the inside of a front end wall of a vacuum chamber; support means attached to said central hub whereby to

1. An apparatus for rotating a transfer plate inside a cylindrical vacuum chamber having front and back end walls and for translating a pressure plate, comprising: a central hub attached to the inside of a front end wall of a vacuum chamber; support means attached to said central hub whereby to support a back end wall of said vacuum chamber; a transfer plate hub assembly attached to a transfer plate, said transfer plate hub assembly being formed around said central hub; a pressure plate hub assembly attached to a pressure plate, said pressure plate hub assembly being formed around said transfer plate hub assembly; a yoke attached to said pressure plate hub assembly and to a ram means for moving said yoke; an actuating means; a means for translating linear motion of said actuating means into rotary motion; a rotary vacuum sealing feedthrough means having an axle which axle has a first end adapted to receive rotary motion from said means for translating linear motion into rotary motion; a ratchet arm attached at a first end to a second end of said axle of said rotary vacuum sealing feedthrough means; a ratchet tip attached to a second end of said ratchet arm; and a transfer plate index socket attached to said transfer plate hub assembly and formed to engage said ratchet tip. 2. An apparatus as claimed in claim 1 where said actuating means is a pneumatic actuator. 3. An apparatus as in claim 1 where said actuating means is an electromechanical actuator. 4. An apparatus as in claim 1 where said means for translating linear motion into rotary motion is a barrel cam. 5. An apparatus as in claim 4 where said actuating means, said barrel cam and said rotary feedthrough are contained in a structural housing. 6. An apparatus as in claim 1 where said rotary feedthrough is a modular magnetic fluid seal incorporating magnetic sealing fluid. 7. An apparatus as in claim 1 where said central hub, transfer plate hub and pressure plate hub are formed as concentric cylindrical shells. 8. An apparatus as in claim 1 where said support means is a pair of bolts threaded into said central hub at the end of said central hub nearest the back end wall of the chamber, the bolts being adjusted so that the bolt heads contact and support the back end wall when vacuum is drawn. 9. An apparatus as in claim 1 where a first bushing is between said axle and said central hub. 10. An apparatus as in claim 9 where second and third bushings are between said central hub and said transfer plate hub. 11. An apparatus as in claim 10 where fourth and fifth bushings are between said transfer plate assembly and said pressure plate hub assembly. 12. An apparatus as in claim 11 where said fifth bushing is positioned to engage said transfer plate index socket as the pressure plate is drawn toward the back end plate of the vacuum chamber. 13. An apparatus as in claim 1 where said ratchet tip has a v-shaped tip and said transfer index socket is formed to engage said tip. 14. An apparatus as in claim 4 where said barrel cam is constructed and adapted to transmit high torque at the beginning and end of each stroke. 15. An apparatus as in claims 9, 10 or 11 where said bushings are made of polyimide. 16. An apparatus for rotating a transfer plate inside a cylindrical vacuum chamber having front and back walls and for translating a pressure plate, comprising: a central cylindrical hub attached to an inside of a front wall of a vacuum chamber; a pair of bolts having heads, said bolts being threaded into said central hub at an end of said central hub nearest the back end wall of the vacuum chamber, said bolts being adjusted so that said bolt heads contact and support the back end wall when vacuum is drawn; a transfer plate hub assembly attached to a transfer plate, said transfer plate hub assembly being formed around said central hub as a cylindrical shell; a pressure plate hub assembly attached to a pressure plate, said pressure plate hub assembly being formed as a cylindrical shell around said transfer plate hub assembly; a yoke attached to said pressure plate hub assembly and to a ram means for moving said yoke; a pneumatic actuator; a barrel cam means for translating linear motion from said actuating means into rotary motion such that the torque output of said barrel cam is high at the beginning and end of each stroke; a rotary vacuum sealing feedthrough of the modular magnetic fluid seal type incorporating magnetic sealing fluid, said feed-through having an axle the first end of which receives rotary motion from said barrel cam; a structural housing for said pneumatic actuator, said barrel cam and said rotary feedthrough; a first bushing between said axial and said central hub; a second and third bushing between said central hub and said transfer plate hub assembly; a fourth and fifth bushing between said transfer plate hub assembly and said pressure plate hub assembly; a ratchet arm attached at a first end to a second end of said axle of said rotary feedthrough; a ratchet tip attached to a second end of said ratchet arm; and a transfer plate index socket attached to said transfer plate hub assembly nearest to the back end wall of said vacuum chamber, said socket being formed to receive said ratchet tip. 17. Apparatus for processing workpieces, said apparatus comprising: a vacuum chamber including a workpiece-loading wall, an opening in said loading wall for receiving workpieces, and door means for closing said opening; said vacuum chamber further including a second wall spaced opposite said loading wall; workpiece-transfer means in said chamber and adapted to carry a plurality of workpieces in spaced circular arrangement; processing means for processing workpieces carried on said transfer means; central hub means inside said chamber and having one end thereof abutting said loading wall, said central hub means being positioned about an axis offset from said opening; means rotatably supporting said transfer means coaxially with said hub means; rotary drive means passing through said central hub means and having a radial extension thereon for rotating said transfer means around said axis, said drive means being adapted to oscillate through an arc of substantially less than 360 degrees; and support means extending between and in contact with the other end of said hub means and second wall, whereby inward bowing of said walls is resisted by said support means and said hub means when the inside of said chamber is below atmospheric pressure, said support means being positioned with respect to said radial extension such that the support means would prevent 360 degrees rotation of the radial extension, but permit said arcuate oscillation. 18. Apparatus for processing workpieces, said apparatus comprising: a vacuum chamber including a workpiece-loading wall, an opening in said loading wall for receiving workpieces, and door means for closing said opening; said vacuum chamber further including a second wall spaced opposite said loading wall; workpiece-transfer means in said chamber and adapted to carry a plurality of workpieces in spaced circular arrangement; pressure plate means in said chamber adjacent said transfer means and on the side of said transfer means opposite said loading wall; processing means for processing workpieces carried on said transfer means; support means inside said chamber and supporting said transfer means for rotation about an axis offset from said opening; means for rotating said transfer means around said axis; ram means connected to said pressure plate means and adapted to move said pressure plate means toward and away from said loading wall; said transfer means being in contact with said pressure plate means when said pressure plate means is moved fully toward said loading wall; first abutment means moveable with said pressure plate means as the pressure plate means is moved toward and away from said loading wall by said ram means, second abutment means associated with said transfer means and positioned for contact by said first abutment means when said pressure plate means is moved away from said loading wall; and said first and second abutment means being spaced apart when said pressure plate means is moved fully toward said loading wall; whereby when said ram means is moved fully toward said loading wall, said transfer means is in contact with said pressure plate means, and when said ram means is moved away from said loading wall said pressure plate means is first moved away from said loading wall to provide a spacing between said pressure plate means and said transfer means, and then continued movement of said pressure plate means moves said transfer means away from said loading wall by contact between said first and second abutment means.