Claims
- 1. A printing apparatus for recording on a recording medium, comprising:
- a rotatable member for feeding a recording medium;
- a motor for driving said rotatable member;
- drive transmission means for transmitting the drive force of said motor to said rotatable member to rotate said rotatable member;
- detent means adapted to assume a restraint state in which rotation of said rotatable member is restrained and a release state in which said restraint state is released thereby permitting rotation of said rotatable member;
- drive means for placing said detent means into the release state, in response to a predetermined signal;
- control means for controlling said detent means and said motor to electrically lock said rotatable member by reducing the voltage applied to said motor to a retaining voltage after said rotatable member is rotated by a predetermined amount by applying a drive voltage to said motor while maintaining said detent means in the release state.
- 2. Printing apparatus according to claim 1, wherein said rotatable member is a platen.
- 3. Printing apparatus according to claim 1, wherein said motor is a stepping motor.
- 4. Printing apparatus according to claim 1, wherein said control means controls said drive means to place said detent means into the release state prior to the start of rotation of said rotatable member by said motor.
- 5. Printing apparatus according to claim 1, wherein said drive means comprises a solenoid comprising a pin, and a lever for engaging and disengaging said detent means to place said detent means in the restraint state and in the release state, wherein said pin is joined with said lever.
- 6. Printing apparatus according to claim 5, wherein said drive means further comprises a spring attached to said lever, for biasing said lever in one direction into engagement with said detent means, wherein displacement of said solenoid in response to an energization signal rotates said lever against the bias of said spring in the opposite direction out of engagement with said detent means.
- 7. Printing apparatus according to claim 6, wherein said lever comprises means for being rotated by said spring in one direction in response to terminating said energization signal to said solenoid.
- 8. Printing apparatus comprising:
- a rotatable member for feeding a printing medium;
- a detent gear of a predetermined gear pitch mounted for rotation with said rotatable member;
- lever means mounted for engaging said detent gear to specify rotation positions of said rotatable member;
- means for locking and releasing the engagement of said lever means to and from said detent gear;
- a stepping motor, which rotates step by step in response to a rotation signal, for rotating said rotatable member, a rotary step of said rotatable member caused by one rotary step of said stepping motor being smaller than the predetermined gear pitch of said detent gear; and
- means for controlling said locking and releasing means to release the engagement of said lever means from said detent gear when the rotatable member is rotated by the stepping motor, and to engage the lever means with the detent gear to lock said rotatable member after said rotatable member is rotated by said stepping motor by an amount which corresponds to a multiple of the predetermined gear pitch of said detent gear and is then stopped, and for controlling said locking and releasing means to maintain said lever means released from said detent gear after said rotatable member is rotated by said stepping motor by an amount which does not correspond to a multiple of the predetermined gear pitch of said detent gear and is then stopped so that said lever means does not normally engage said detent gear, wherein said rotational position of said stepping motor is retained in response to a retention signal.
- 9. A printing apparatus according to claim 8, wherein said locking and releasing means comprises means for releasing the engagement of said detent gear and said lever means prior to the start of a rotation signal for said stepping motor.
- 10. A printing apparatus according to claim 8, wherein said stepping motor comprises means for initially receiving a determined voltage and means for then receiving a lower voltage.
- 11. The apparatus defined by claim 10, wherein said receiving means comprises means for initially receiving said determined voltage comprising a voltage of said rotation signal and means for then receiving said lower voltage comprising a voltage of said retention signal.
- 12. Printing apparatus according to claim 8, wherein the rotary step of said rotatable member caused by one rotary step of said stepping motor is a fraction of a minimum rotary step of said rotatable member provided by the predetermined gear pitch of said detent gear.
- 13. The apparatus defined by claim 8 wherein said locking and releasing means comprises a solenoid comprising a pin adapted to engage and disengage said lever means.
- 14. The apparatus defined by claim 13, wherein said locking and releasing means further comprises a spring attached to said lever means for biasing said lever means in one direction into engagement with said detent gear, wherein displacement of said solenoid in response to an energization signal rotates said lever means against the bias of said spring in the opposite direction out of engagement with said detent gear.
- 15. The apparatus defined by claim 14, wherein said lever means comprises means for being rotated by said spring in said one direction in response to terminating said energizing current to said solenoid.
Priority Claims (1)
Number |
Date |
Country |
Kind |
58-89981 |
May 1983 |
JPX |
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Parent Case Info
This application is a continuation of application Ser. No. 193,164, filed May 6, 1988, now abandoned, which is a continuation of Ser. No. 068,726, filed July 1, 1987, now abandoned, which is a continuation of Ser. No. 807,787, filed Dec. 12, 1985, now abandoned, which is a continuation of Ser. No. 605,840, filed May 1, 1984, now abandoned.
US Referenced Citations (17)
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Oct 1981 |
EPX |
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Non-Patent Literature Citations (2)
Entry |
IBM Technical Disclosure Bulletin, vol. 19, No. 8, Jan. 1977, pp. 2974-2975, "Stepping Motor Stop Control" by Barnett et al. |
IBM Technical Bulletin, vol. 17, No. 4, "Electromechanical Variable-Index System", pp. 959-960, Sep. 1974. |
Continuations (4)
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Number |
Date |
Country |
Parent |
193164 |
May 1988 |
|
Parent |
68726 |
Jul 1987 |
|
Parent |
807787 |
Dec 1985 |
|
Parent |
605840 |
May 1984 |
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