Patent US3672246A successfully refreshed from Google Patents.
US3672246A
Expired / Lapsed
US
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Automatic spindle growth compensation system
Assignee: United States Atomic Energy Commission
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Filing: 1970-04-20
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Granted: 1972-06-27
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Expires: 1990-04-20
Abstract
Abstract A numerically controlled lathe is provided with a spindle growth compensator which continuously monitors the spindle growth using a displacement sensing device with a linear electrical output signal. The signal is them modified and used in the numerically controlled machine tool control unit to offset the programmed carriage position, thereby continuously compensating for spindle growth.
Inventors
- 👤 Hubert P Prewett Jr
- 👤 Charles H Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:56
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/404; G05B2219/00; G05B2219/30; G05B2219/49; G05B2219/49169; Y; Y10; Y10T; Y10T409/00; Y10T409/30; Y10T409/30084; Y10T409/300896; Y10T82/00; Y10T82/25; Y10T82/2502
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
357 words
A spindle growth compensating system for use with a numerically controlled lathe, said lathe including a headstock, a spindle extending from and supported by said headstock, a chuck coupled to said spindle and for holding a workpiece, a housing encompassing said chuck and affixed thereto, a carriage ways, a carriage slidable on said carriage ways, said carriage supporting a cutting tool, a Y-axis lead screw, a torque motor, said Y-axis lead screw being mechanically coupled to said motor and threadably coupled to said tool supporting carriage, said carriage adapted to be moved along the Y-axis of said lathe by said lead screw, said system including numerical control signal means for controlling said torque motor which in turn drives said lead screw to effect the positioning of said tool supporting carriage along said Y-axis in accordance with a Y-axis position error signal, a circular adapter plate permanently mounted on and encompassing said chuck housing and a portion of said spindle, an air nozzle fixedly mounted on said carriage ways by means of a support post, said adapter plate provided with a side face which faces the exit end of said air nozzle to provide a reference surface for said air nozzle, said air nozzle positioned a fixed selected distance from said adapter plate side at startup operation of Said lathe, a source of air, means for supplying air from said air source at a selected flow rate to said air nozzle, means coupled to the air input to said air nozzle for sensing the backpressure from said nozzle and producing an electrical signal with an amplitude proportional to any relative movement in a Yaxial direction between said plate side and said air nozzle due to spindle growth during lathe operation, means for scaling said signal, and means for summing said scaled signal with the Y-axis numerical control position error signal, the output of said summing means connected to said motor, thereby automatically effecting the repositioning of said tool supporting carriage along the Y-axis of said lathe by means of said Y-axis lead screw on a continuous basis to compensate for said spindle growth during operation of said lathe.
Claim 2
Dependent Claim
357 words
A spindle growth compensating system for use with a numerically controlled lathe, said lathe including a headstock, a spindle extending from and supported by said headstock, a chuck coupled to said spindle and for holding a workpiece, a housing encompassing said chuck and affixed thereto, a carriage ways, a carriage slidable on said carriage ways, said carriage supporting a cutting tool, a Y-axis lead screw, a torque motor, said Y-axis lead screw being mechanically coupled to said motor and threadably coupled to said tool supporting carriage, said carriage adapted to be moved along the Y-axis of said lathe by said lead screw, said system including numerical control signal means for controlling said torque motor which in turn drives said lead screw to effect the positioning of said tool supporting carriage along said Y-axis in accordance with a Y-axis position error signal, a circular adapter plate permanently mounted on and encompassing said chuck housing and a portion of said spindle, an air nozzle fixedly mounted on said carriage ways by means of a support post, said adapter plate provided with a side face which faces the exit end of said air nozzle to provide a reference surface for said air nozzle, said air nozzle positioned a fixed selected distance from said adapter plate side at startup operation of Said lathe, a source of air, means for supplying air from said air source at a selected flow rate to said air nozzle, means coupled to the air input to said air nozzle for sensing the backpressure from said nozzle and producing an electrical signal with an amplitude proportional to any relative movement in a Yaxial direction between said plate side and said air nozzle due to spindle growth during lathe operation, means for scaling said signal, and means for summing said scaled signal with the Y-axis numerical control position error signal, the output of said summing means connected to said motor, thereby automatically effecting the repositioning of said tool supporting carriage along the Y-axis of said lathe by means of said Y-axis lead screw on a continuous basis to compensate for said spindle growth during operation of said lathe.
Claim 3
Dependent Claim
27 words
The system set forth in claim 1, wherein said means for sensing said backpressure from said air nozzle and producing an electrical signal is a pneumatic-to-electrical transducer.
Claim 4
Dependent Claim
63 words
The system set forth in claim 2, wherein said means for supplying air to said air nozzle at a selected flow rate includes a pressure control valve, and a variable orifice valve connected between said nozzle and said air source, a nozzle pressure indicator coupled to the air input to said nozzle, and a pressure regulator indicator coupled across said pressure control valve.
Claim 5
Dependent Claim
78 words
The system set forth in claim 2, wherein said scaling means includes an amplifier and demodulator unit coupled to the output of said transducer, an operational amplifier coupled to the output of said amplifier and demodulator unit, and potentiometer means associated with said operational amplifier for adjusting the output therefrom to zero with said fixed selected distance between said nozzle and adapter plate at said startup, the output of said operational amplifier being coupled to said summing means.
Claim 6
Dependent Claim
43 words
The system set forth in claim 4, wherein there is further included a relay, said relay, when energized, effecting the coupling of said operational amplifier output to said summing means, the operation of said relay being controlled by said numerical control signal means.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |