Patent US2430921A successfully refreshed from Google Patents.
US3676651A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rapid retract for thread cutting
Assignee: Bendix Corp
•
Filing: 1970-09-21
•
Granted: 1972-07-11
•
Expires: 1990-09-21
Abstract
Abstract A numerical control system for performing a thread cutting operation on a lathe and responding to programmed path and final position coordinates to immediately execute a rapid tool retraction whenever one of the two controlled axes is in the final coordinate position.
Inventors
- 👤 George H Mcdaniel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:40
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/182; G05B19/186; G05B2219/00; G05B2219/30; G05B2219/34; G05B2219/34041; G05B2219/43; G05B2219/43152; G05B2219/45; G05B2219/45141; Y; Y10; Y10T; Y10T409/00; Y10T409/30; Y10T409/300056; Y10T409/300168; Y10T409/300336; Y10T409/30084; Y10T409/300896; Y10T409/309576; Y10T409/309856
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
182 words
In a numerical control system for a machine having an element movable along at least two axes, a rapid tool retractor subsystem for withdrawing a tool from a workpiece at the end of a prescribed operation on said workpiece and comprising: first means responsive to program data for moving the element at a first relatively slow rate along a path wherein said tool engages the workpiece and having a component lying along at least one of the axes; second means for storing program data specifying final position coordinates of the element along the axes; said final position coordinates defining the end of a total tool displacement path including a first path portion in engagement with the workpiece and a retract path portion not in engagement with the workpiece, and third means responsive to the element reaching a final position coordinate along said one axis signifying the end of said first path portion of tool displacement to move the element to the final position coordinate along the other axis at a second relatively fast rate to accomplish the retract portion of tool displacement.
Claim 2
Dependent Claim
182 words
In a numerical control system for a machine having an element movable along at least two axes, a rapid tool retractor subsystem for withdrawing a tool from a workpiece at the end of a prescribed operation on said workpiece and comprising: first means responsive to program data for moving the element at a first relatively slow rate along a path wherein said tool engages the workpiece and having a component lying along at least one of the axes; second means for storing program data specifying final position coordinates of the element along the axes; said final position coordinates defining the end of a total tool displacement path including a first path portion in engagement with the workpiece and a retract path portion not in engagement with the workpiece, and third means responsive to the element reaching a final position coordinate along said one axis signifying the end of said first path portion of tool displacement to move the element to the final position coordinate along the other axis at a second relatively fast rate to accomplish the retract portion of tool displacement.
Claim 3
Dependent Claim
15 words
Apparatus as defined in claim 1 including a tape reader for supplying the program data.
Claim 4
Dependent Claim
67 words
Apparatus as defined in claim 1 wherein the third means includes feedback means for producing actual position signals for the element along each of the axes, comparator means for comparing the actual position signals to the program data from the second means and producing an identity signal when said signals are equal, and means responsive to an identity signal to move the element at a maximum rate.
Claim 5
Dependent Claim
20 words
Apparatus as defined in claim 3 including gate means for conducting the identity signal only during a thread cutting operation.
Claim 6
Dependent Claim
79 words
Apparatus as defined in claim 3 including coincidence gates for each of the axes, bistable switch means for each axis and responsive to program data from the respective axes to assume set conditions, the switch means being connected to respective coincidence gates to enable the gates when in the set condition, the gates being connected to receive an identity signal from respective axes, and additional gate means for conducting an identity signal from either of the coincidence gates enabled.
Claim 7
Dependent Claim
24 words
Apparatus as defined in claim 5 including means for resetting the bistable switch means when the element reaches both of the final position coordinates.
Claim 8
Dependent Claim
33 words
Apparatus as defined in claim 1 wherein the first means includes interpolator means for each axis responsive to position commands and feedrate pulses to produce command pulses for application to an element-positioning mechanism.
Claim 9
Dependent Claim
27 words
Apparatus as defined in claim 7 including a spindle pulse transducer for producing feedrate pulses at a rate related to the spindle rotation rate of the machine.
Claim 10
Dependent Claim
41 words
Apparatus as defined in claim 8 wherein tHe third means includes feedrate control means responsive to the element reaching a final position coordinate along said one axis for producing control pulses at a maximum traverse rate thereby overriding said feedrate pulses.
Claim 11
Dependent Claim
22 words
Apparatus as defined in claim 9 including means for discontinuing said control pulses when the element reaches the other final position coordinate.
References Cited (Backward Citations)
US3417303A
Cited
US3428876A
Cited
US3383573A
Cited
US3479574A
Cited
US3538315A
Cited
US3557350A
Cited
US3579070A
Cited
US3582749A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |