US4259625A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotational direction indicating apparatus
Assignee: Sony Corp
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Filing: 1978-05-22
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Granted: 1981-03-31
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Expires: 1998-05-22
Abstract
Abstract A direction indicator for use in apparatus which includes a rotary member whose direction of rotation is determined by a command signal, the direction indicator providing an indication of the commanded direction just as, or momentarily prior to, the rotary member commences rotation in the commanded direction. A frequency generator generates a signal whose frequency is representative of the actual speed of the rotary member. A speed detector coupled to the frequency generator produces a pulse signal when the speed of the rotary member is less than a predetermined speed. A circuit is responsive to the direction command signal and is actuated by the pulse signal to provide an indicating signal corresponding to the direction of rotation determined by the command signal. The resultant indicating signal corresponds substantially to the actual direction of rotation of the rotary member.
Inventors
- 👤 Akira Hatakeyama
- 👤 Atsuo Matsuyama
- 👤 Yutaka Moritake
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:43
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/02; G11B15/05; G11B15/093; Y; Y10; Y10S; Y10S388/00; Y10S388/90; Y10S388/901
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
114 words
In apparatus including a rotary member whose direction of rotation is determined by a command signal, indicating means comprising frequency generating means for sensing the actual speed of said rotary member to produce a speed representing signal whose frequency is representative of the actual speed of said rotary member; speed detecting means coupled to said frequency generating means for producing a pulse signal when the speed of said rotary member is less than a predetermined speed; and means responsive to said command signal and actuated by said pulse signal to provide an indicating signal corresponding to the direction of rotation determined by said command signal at the time that said pulse signal is produced.
Claim 2
Dependent Claim
114 words
In apparatus including a rotary member whose direction of rotation is determined by a command signal, indicating means comprising frequency generating means for sensing the actual speed of said rotary member to produce a speed representing signal whose frequency is representative of the actual speed of said rotary member; speed detecting means coupled to said frequency generating means for producing a pulse signal when the speed of said rotary member is less than a predetermined speed; and means responsive to said command signal and actuated by said pulse signal to provide an indicating signal corresponding to the direction of rotation determined by said command signal at the time that said pulse signal is produced.
Claim 3
Dependent Claim
58 words
The apparatus of claim 1 wherein said command signal is a bi-state signal having one state to determine rotation in a first direction and a second state to determine rotation in a second, opposite direction; and wherein said indicating signal also is a bi-state signal whose state indicates substantially the actual direction of rotation of said rotary member.
Claim 4
Dependent Claim
41 words
The apparatus of claim 2 wherein said means to provide an indicating signal comprises sampling means responsive to said pulse signal for sampling said command signal, thereby to provide said indicating signal corresponding to the state of said sampled command signal.
Claim 5
Dependent Claim
48 words
The apparatus of claim 3 wherein said sampling means comprises a triggerable flip-flop circuit having a data input terminal connected to receive said command signal and a trigger input terminal responsive to said pulse signal to actuate said flip-flop circuit to a state corresponding to said command signal.
Claim 6
Dependent Claim
116 words
The apparatus of claim 4 wherein said frequency generating means includes pulse generating means for generating a train of pulses having a repetition rate proportional to said actual speed of said rotary member; and wherein said speed detecting means comprises monostable multivibrator means having a time constant substantially equal to the separation between successive ones of said pulses which are generated when said rotary member rotates at said predetermined speed, said monostable multivibrator means being coupled to said pulse generating means and actuated to its unstable state in response to each pulse, whereby said pulse signal is produced when said monostable multivibrator means returns to its stable state at the conclusion of the time constant thereof.
Claim 7
Dependent Claim
90 words
The apparatus of claim 5 wherein said speed detecting means further comprises another flip-flop circuit having a data input terminal connected to receive the output of said monostable multivibrator means and a trigger input terminal responsive to said generated pulses to actuate said another flip-flop circuit to a state corresponding to the state of said monostable multivibrator, thereby producing said pulse signal at the output of said another flip-flop circuit with a duration equal to the time that the speed of said rotary member is less than said predetermined speed.
Claim 8
Dependent Claim
67 words
The apparatus of claim 6 wherein said pulse generating means comprises a disc secured to said rotary member and having spaced magnetic elements thereon, a magnetic pick-up sensor fixed with respect to said disc to sense said magnetic elements as said disc rotates so as to produce corresponding pulses, and pulse shaping means coupled to said magnetic pick-up sensor for shaping said pulses to have uniform duration.
Claim 9
Dependent Claim
177 words
In a motor control system of the type having a motor for driving a rotary member, a source of command signals to determine the operating condition and direction of rotation of said motor, and a motor control circuit responsive to said command signals for selectively energizing said motor, apparatus comprising frequency generating means for sensing the actual speed of said rotary member to produce a speed representing signal whose frequency is representative of the actual speed of said rotary member; speed detecting means coupled to said frequency generating means for producing a pulse signal when the speed of said rotary member is less than a predetermined speed; means responsive to a direction command signal and actuated by said pulse signal to provide an indicating signal corresponding to the direction of rotation commanded by said direction command signal at the time that said pulse signal is produced; and means responsive to said indicating signal for supplying an aiding signal to said motor control circuit in aiding relation to said command signal for supplementing the energization of said motor.
Claim 10
Dependent Claim
177 words
In a motor control system of the type having a motor for driving a rotary member, a source of command signals to determine the operating condition and direction of rotation of said motor, and a motor control circuit responsive to said command signals for selectively energizing said motor, apparatus comprising frequency generating means for sensing the actual speed of said rotary member to produce a speed representing signal whose frequency is representative of the actual speed of said rotary member; speed detecting means coupled to said frequency generating means for producing a pulse signal when the speed of said rotary member is less than a predetermined speed; means responsive to a direction command signal and actuated by said pulse signal to provide an indicating signal corresponding to the direction of rotation commanded by said direction command signal at the time that said pulse signal is produced; and means responsive to said indicating signal for supplying an aiding signal to said motor control circuit in aiding relation to said command signal for supplementing the energization of said motor.
Claim 11
Dependent Claim
43 words
The apparatus of claim 8 wherein said means for supplying an aiding signal comprises pulse producing means for producing a braking pulse supplied to said motor control circuit when said command signal commands a change in the direction of rotation of said motor.
Claim 12
Dependent Claim
56 words
The apparatus of claim 9 wherein said means for producing a braking pulse is responsive to a change in state of said direction command signal, representing a commanded change in direction of rotation, to initiate said braking pulse, and is responsive to a change in the state of said indicating signal to terminate said braking pulse.
Claim 13
Dependent Claim
51 words
The apparatus of claim 9 wherein said means for producing a braking pulse comprises exclusive-OR means having one input connected to receive said direction command signal and another input connected to receive said indicating signal for producing said braking pulse when said direction command and indicating signals differ from each other.
Claim 14
Dependent Claim
66 words
The apparatus of claim 9 wherein said motor control system is used in a tape drive system, said rotary member is a capstan for driving said tape, and said apparatus further includes a selectively energized pinch roller for engaging said tape and capstan to enable said capstan to drive said tape, and pinch roller control means responsive to said braking pulse for de-energizing said pinch roller.
Claim 15
Dependent Claim
62 words
The apparatus of claim 12 wherein said pinch roller control means comprises OR-gate means having one input connected to receive said braking pulse and another input connected to receive said pulse signal produced by said speed detecting means for producing a de-energizing pulse having a duration substantially equal to the duration of said braking pulse plus the duration of said pulse signal.
Claim 16
Independent Claim
114 words
The apparatus of any one of claims 8, 9, 10, 11, 12 or 13 wherein said direction command signal is a bi-state signal having one state to determine rotation in a first direction and a second state to determine rotation in a second, opposite direction; said indicating signal also is a bi-state signal whose state indicates substantially the actual direction of rotation of said rotary member; and said means to provide an indicating signal comprises triggerable flip-flop means having a data input terminal connected to receive said direction command signal and a trigger input terminal responsive to said pulse signal to actuate said flip-flop means to a state corresponding to said direction command signal.
Claim 17
Dependent Claim
115 words
The apparatus of claim 14 wherein said frequency generating means includes pulse generating means for generating a train of pulses having a repetition rate proportional to said actual speed of said rotary member; and said speed detecting means comprises monostable multivibrator means having a time constant substantially equal to the separation between successive ones of said pulses which are generated when said rotary member rotates at said predetermined speed, said monostable multivibrator means being coupled to said pulse generating means and actuated to its unstable state in response to each pulse, whereby said pulse signal is produced when said monostable multivibrator means returns to its stable state at the conclusion of the time constant thereof.
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) | 1984-03-30 | 1984-09-29 | 1985-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-30 | 1988-09-29 | 1989-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-30 | 1992-09-29 | 1993-03-31 | $7700.00 | Window Closed / Lapsed |