US3817129A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Numerically controlled threadcutting system
Assignee: Toyoda Koki KK
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Filing: 1972-09-15
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Granted: 1974-06-18
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Expires: 1992-09-15
Abstract
Abstract A numerically controlled threadcutting system includes a computer, a stepping motor which actuates a cutter along a workpiece, a position coder which generates a series of output pulse signals in accordance with the rotational speed of the workpiece, a shift register and a counter. Interpolated data for threadcutting is memorized in order in the memory of the computer. The interpolation data in the memory is transferred into the shift register one unit by one unit. A unit consists of a predetermined number of binary coded signals. The contents of the shift register are provided to the stepping motor one bit by one bit for controlling the longitudinal movement of the cutter when triggered by the pulse signals from the position coder. When the number of shifts or shift times counter by the counter reaches a predetermined value, the next new unit of the interpolation data in the memory is transferred into the shift register, whereby the transverse movement of the cutter is controlled synchronously with the rotation of the workpiece so as to machine a thread of a predetermined pitch thereon with high accuracy.
Inventors
- 👤 H Nishimura
- 👤 K Kanou
- 👤 S Kato
- 👤 T Ishigaki
- 👤 T Hosotani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:03
CPC Classifications
B; B23; B23G; B23G3/00; G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/182; G05B19/186; Y; Y10; Y10T; Y10T82/00; Y10T82/10; Y10T82/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
240 words
A numerically controlled thread cutting system comprising; a cutter for cutting a thread on a workpiece; workpiece supporting means for rotatably supporting said workpiece; first driving means for rotating said workpiece; second driving means for effecting a longitudinal relative movement between said workpiece and said cutter; third driving means for effecting a transverse relative movement between said workpiece and said cutter; pulse generating means connected to said first driving means for generating first pulses in response to a rotational angle of said workpiece; memory means having a plurality of addresses respectively including a predetermined number of binary bits, said addresses respectively memorizing a series of interpolation pulse signals for a threadcutting operation by one unit thereof in order; and control means having at least one shift register for receiving said interpolation pulse signals one unit by one unit from said memory means, said unit of interpolation pulse signals in said shift register being provided to said second driving means one bit by one bit in order synchronously with said first pulses, counter means for generating a signal serving to transfer the next unit of said interpolation pulse signals from said memory means into said shift register when said first mentioned unit of interpolation pulse signals in said shift register has been completely provided to said second driving means, and means for controlling a stopping of the threadcutting operation when the thread is formed to a predetermined length on said workpiece.
Claim 2
Dependent Claim
240 words
A numerically controlled thread cutting system comprising; a cutter for cutting a thread on a workpiece; workpiece supporting means for rotatably supporting said workpiece; first driving means for rotating said workpiece; second driving means for effecting a longitudinal relative movement between said workpiece and said cutter; third driving means for effecting a transverse relative movement between said workpiece and said cutter; pulse generating means connected to said first driving means for generating first pulses in response to a rotational angle of said workpiece; memory means having a plurality of addresses respectively including a predetermined number of binary bits, said addresses respectively memorizing a series of interpolation pulse signals for a threadcutting operation by one unit thereof in order; and control means having at least one shift register for receiving said interpolation pulse signals one unit by one unit from said memory means, said unit of interpolation pulse signals in said shift register being provided to said second driving means one bit by one bit in order synchronously with said first pulses, counter means for generating a signal serving to transfer the next unit of said interpolation pulse signals from said memory means into said shift register when said first mentioned unit of interpolation pulse signals in said shift register has been completely provided to said second driving means, and means for controlling a stopping of the threadcutting operation when the thread is formed to a predetermined length on said workpiece.
Claim 3
Dependent Claim
15 words
A threadcutting system as in claim 1, wherein said second driving means is a servomotor.
Claim 4
Dependent Claim
30 words
A threadcutting system as in claim 2, wherein said pulse generator generates second pulse signals for starting the threadcutting operation at an original and predetermined rotational position of said workpiece.
Claim 5
Dependent Claim
14 words
A threadcutting system as in claim 2, wherein said servomotor is a stepping motor.
Claim 6
Dependent Claim
351 words
A numerically controlled threadcutting system comprising: a cutter slidably mounted on a cutter supporting means in a longitudinal and a transverse direction with respect to a workpiece for cutting a thread on a workpiece; workpiece supporting means mounted on a bed for rotatably supporting said workpiece; an electric motor mounted on said workpiece supporting means for continuously rotating said workpiece; a second stepping motor mounted on said cutter supporting means for feeding said cutter in said transverse direction against said workpiece; pulse generating means mounted on said workpiece supporting means for generating first and second pulse signals in accordance with a rotational angle of said workpiece, said first pulse signals being of a predetermined number of pulses per one revolution of said workpiece and said second pulse signals being generated by one pulse per one revolution of said workpiece; memory means for memorizing a series of interpolation pulse signals for machining said thread at a predetermined pitch on said workpiece; control means having at least one shift register for receiving a unit of said interpolation pulse signals from said memory means, said unit of interpolation pulse signals in said shift register being provided one bit by one bit to said first stepping motor for driving the same synchronously with said first pulse signals and being shifted one bit by one bit by said first pulse signals, counter means for sensing an output completion of whole bits of said unit of interpolation pulse signals in said shift register and for generating a signal for serving to transfer a next unit of said interpolation pulse signals in said memory means into said shift register, presettable counter means for controlling to stop a threadcutting operation when the thread is of a predetermined length corresponding to a preset value therein, means for controlling to start said threadcutting operation at an original and predetermined rotational position of said workpiece by means of said second pulse signals supplied from said pulse generating means, and infeed control means for controlling said second stepping motor so as to obtain a predetermined transverse movement of said cutter against said workpiece.
Claim 7
Dependent Claim
351 words
A numerically controlled threadcutting system comprising: a cutter slidably mounted on a cutter supporting means in a longitudinal and a transverse direction with respect to a workpiece for cutting a thread on a workpiece; workpiece supporting means mounted on a bed for rotatably supporting said workpiece; an electric motor mounted on said workpiece supporting means for continuously rotating said workpiece; a second stepping motor mounted on said cutter supporting means for feeding said cutter in said transverse direction against said workpiece; pulse generating means mounted on said workpiece supporting means for generating first and second pulse signals in accordance with a rotational angle of said workpiece, said first pulse signals being of a predetermined number of pulses per one revolution of said workpiece and said second pulse signals being generated by one pulse per one revolution of said workpiece; memory means for memorizing a series of interpolation pulse signals for machining said thread at a predetermined pitch on said workpiece; control means having at least one shift register for receiving a unit of said interpolation pulse signals from said memory means, said unit of interpolation pulse signals in said shift register being provided one bit by one bit to said first stepping motor for driving the same synchronously with said first pulse signals and being shifted one bit by one bit by said first pulse signals, counter means for sensing an output completion of whole bits of said unit of interpolation pulse signals in said shift register and for generating a signal for serving to transfer a next unit of said interpolation pulse signals in said memory means into said shift register, presettable counter means for controlling to stop a threadcutting operation when the thread is of a predetermined length corresponding to a preset value therein, means for controlling to start said threadcutting operation at an original and predetermined rotational position of said workpiece by means of said second pulse signals supplied from said pulse generating means, and infeed control means for controlling said second stepping motor so as to obtain a predetermined transverse movement of said cutter against said workpiece.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |