JP2603930B2 - Recording device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus, and more particularly to a recording apparatus that switches and transmits a driving force of a pulse motor to a plurality of driving systems via a clutch mechanism.

2. Description of the Related Art Conventionally, a recording apparatus using a configuration in which a plurality of driven members are driven by a single motor has been known. In this type of device, the power of the motor is transmitted to a plurality of drive systems using a switching means such as a clutch.

FIG. 3 shows the structure of a conventional recording apparatus of this type. Here, a configuration of a type impact print in which a type of a type wheel 3 is hit by a print hammer 4 and is made to contact a recording medium 2 such as paper wound around a platen 1 for recording is performed.

In the illustrated configuration, the power of the feed motor 11 is switched by the clutch 12, and recording sub-scanning by the platen,
It is used both for driving the ink ribbon and the correction ribbon of the recording head.

The recording head includes a type wheel 3, a printing hammer 4, and a ribbon cassette 8, and is mounted on a carrier 5. The carrier 5 is slidably supported left and right on a shaft 6 and a guide rail 9 parallel to the platen 1.
The carrier 5 is connected to a motor 10 via a belt 7, and is moved to a predetermined printing position by driving the motor 10.

On the other hand, a gear 15 composed of a spur gear is connected to the shaft of the platen 1, and the gear 15, the clutch 12, the pinion gear
It is driven by the feed motor 11 via 11a.

The clutch 12 is configured to be movable to a position indicated by a solid line or a two-dot chain line by a clutch solenoid 13, and transmits power to either the gear 15 or the pulley 16.

The pulley 16 is connected to a pulley 17a via a belt 17. The pulley 17a rotates the control rod 18.

The control rod 18 is coupled to a coupling portion (not shown) of the recording head, and the rotation of the control rod 18 carries the ribbon of the ink ribbon cassette 8 or the transport of a correction ribbon (not shown in a typewriter or the like).

[Problems to be Solved by the Invention] FIGS. 4 and 5 show the clutch mechanism in detail. FIG. 4 is an exploded perspective view of the clutch unit, and FIG. 5 is a sectional view.

The clutch mechanism is clutch 20, clutch spring 21,
It comprises a clutch body 12a and a clutch pulley 16, which are assembled on a clutch shaft 19 as shown in FIG.

The clutch body 12a is constantly urged in the direction of arrow 22a by a clutch spring 21, and a gear 1 formed on the outer periphery of the clutch from the pinion 11a of the feed motor 11.
The torque transmitted via 2b is applied to the clutch pulley by engagement of the conical serrations 12c and 16a.
16 to communicate.

On the other hand, the clutch solenoid 13 has a substantially Y-shaped lever 14.
4 and 5 against the clutch spring 21.
Serrations 12c and 16a are separated by sucking into b,
Conversely, serrations 12d and 20a are engaged, and clutch gear 20
To transmit power. The clutch gear 20 is a coaxial gear 15a, 1
The rotation is transmitted to the gear 15 via 5b (FIG. 4), and the platen 1 is driven via the reduction mechanism by these.

When the excitation of the solenoid 13 is released, the clutch spring 21
As a result, the clutch 12a moves in the direction of the arrow 22a, power is transmitted to the clutch pulley 16, and the control rod 18 is rotated.

In the above configuration, it is easy to use a pulse motor capable of holding the control position as the feed motor 11. However, when the feed motor 11 is constituted by a pulse motor, the rotation of the motor is naturally stopped at the time of clutch switching, but depending on the accuracy of the constituent members, the pinion gear and the gear portion of the clutch are driven by the stopping torque of the motor.
There may be no play during 12a and the clutch may not move smoothly. When the clutch is restored, the clutch may not be able to be restored only by the force of the clutch spring.

When the operation of the clutch is incomplete as described above, there is a problem that a paper feeding operation by the platen, an ink ribbon conveyance operation, and the like may malfunction.

[Means for Solving the Problems] In order to solve the above problems, according to the present invention, a driving gear for transmitting a driving force of a pulse motor is meshed with a first gear of a clutch mechanism, and a clutch is provided. At the time of switching, the first gear is moved while meshing with the drive gear to switch the meshing from one of the second gear and the third gear of the clutch mechanism to the other, and is interlocked with the second gear. In a recording apparatus that transmits a driving force of a pulse motor to a first driving system or a second driving system interlocked with a third gear, when a clutch is switched by the clutch mechanism,
Control means is provided for interrupting the holding excitation of the pulse motor in the drive stop state, and for performing the switching operation by moving the first gear of the clutch mechanism in a state of being engaged with the drive gear during the interruption period. The configuration was adopted.

[Operation] According to such a configuration, at the time of clutch switching,
The switching excitation is performed by interrupting the holding excitation of the pulse motor in the drive stop state and moving the first gear of the clutch mechanism while meshing with the driving gear during this interruption period. Since no excessive force is applied to the transmission mechanism, the clutch can be switched reliably.

EXAMPLES Hereinafter, the present invention will be described in detail based on examples shown in the drawings. However, it is assumed that the following embodiment has the same recording mechanism drive system as that shown in FIGS. 3 to 5.

FIG. 1 shows the configuration of a control system for controlling the mechanisms shown in FIGS.

In the figure, reference numeral 23 denotes an input control circuit, which comprises a keyboard in the case of an electronic typewriter and an interface circuit in the case of a recording device such as a word processor or a computer system, and inputs recording data to be printed. The control system mainly includes a control logic circuit 29 and a print control circuit 36.

The control logic circuit connects an MPU (microprocessor) 24, a memory, a timer, and the like via a bus, and controls the operation of the entire device. As the memory, a ROM 25 and a RAM 26 storing a control program of the apparatus are provided. In the RAM 26, a register for storing a control variable is provided.

The timer 27 is used to generate a time signal required for various recording controls.

The print control circuit 36 is connected via the input / output extension circuit 28. The control circuit 36 is constituted by a mechanism section including the feed motor 11, the clutch solenoid 13, and other sensors and the motor 35, and drivers (drive circuits including switching transistors) 30 to 31 that respectively control these mechanisms. Be composed.

FIG. 2A shows the feed motor 11 having the above configuration.
And a drive voltage waveform of the clutch solenoid.

In FIG. 2A, reference numeral C denotes a rotation of the feed motor 11 by the clutch 12 via the clutch pulley 16 by the control rod.
The reference symbol P indicates a period during which rotation is transmitted to the platen 1 via the clutch gear 20, while the period is transmitted to the 18 side. As shown in the drawing, the clutch solenoid 13 is turned on during the period in which the sub-scan is performed by rotating the platen 1, and the clutch solenoid 13 is turned off in the main scanning period during which the control rod 18 is rotated.

In the present embodiment, as shown, the clutch solenoid 13
Before and after switching, that is, the clutch solenoid
Time T3 when drive voltage of 13 rises, clutch solenoid
The excitation current of the feed motor 11 is cut off during periods T2 to T4 and T7 to T9 sandwiching the time T8 at which the drive voltage of FIG.

The feed motor 11 is operated for periods C and P (up to T1, T5 to T6, T10
In (1) to (4), the ink ribbon is rotated by a rotation amount necessary for transporting or sub-scanning, and the holding excitation is performed to stop the rotation before and after the excitation interruption periods T2 to T4 and T7 to T9 for switching the clutch solenoid 13. That is, the feed motor 11 holds the control position by the holding excitation current.

When the excitation of the clutch solenoid 13 starts at time T3,
The clutch solenoid 13 is moved by the lever 14 to the clutch body.
12a is moved to the clutch gear 20 side, and at time T3 ', the serrations 12b and 20a are completely engaged.

In the present embodiment, in the period T2 to T4, the feed motor
Since the excitation of the motor 11 is stopped and there is play between the gear 12b of the clutch body and the pinion gear 11a of the feed motor 11, the clutch solenoid 13 easily moves the clutch body 12a toward the clutch gear 20 with a small force. be able to.

On the other hand, when the clutch solenoid 13 is cut off at time T8, the excitation of the feed motor 11 is also cut off at this time, so that the clutch main body 12a easily returns only by the force of the clutch spring 21 to engage the serrations 12c and 16a. be able to.

Such an operation can be performed by controlling the operations of the feed motor 11 and the clutch solenoid 13 in conjunction with each other by the MPU 24. FIG. 2B shows a control procedure of the MPU 24 for performing the above-described clutch switching operation. This procedure is the control procedure of MPU24.
Stored in OM25.

When performing clutch switching, the MPU 24 stores the excitation phase of the feed motor 11 in step S1 of FIG. 2 (B). The excitation phase data is stored in a register of the RAM 26.

Next, in step S2, the excitation of the feed motor 11 is cut off (time T2 or T7 in FIG. 2A).

In step S3, times T2 to T3 to T7 to T7 in FIG.
Wait for the appropriate time allotted for T8. The wait time is controlled by the timer 27.

In step S4, the excitation state of the clutch solenoid 13 is switched from time T3 to time T8 in FIG. 2A (ON at time T3 and OFF at time T8).

In step S5, the process waits again. The time at this time is a time T3 to T3 'at which the clutch switching by the clutch solenoid 13 is completely performed, or a time (T3 to T4 or T8 to T9) in which an appropriate margin is taken into consideration for T8 to T8'.

In step S6, the excitation of the feed motor 11 is started from time T4 to time T9 in FIG. 2A, and the excitation phase at this time is made to match the excitation phase before excitation shutoff stored in the register of the RAM 26.

According to the above-described processing, the control is performed so that the excitation phases coincide before and after the excitation cutoff period of the feed motor 11, so that the sub-scanning accuracy by the platen 1 or the conveyance accuracy of the ink ribbon and the like by the control rod 18 are achieved. Is not reduced.

The above configuration is not limited to the type impact printer, but can be applied to various recording apparatuses.

[Effects of the Invention] As is clear from the above description, according to the present invention, the drive gear transmitting the driving force of the pulse motor meshes with the first gear of the clutch mechanism, and the first gear of the clutch mechanism is switched when the clutch is switched. A first drive system interlocked with the second gear is switched by moving the first gear while meshing with the drive gear to switch from one of the second gear and the third gear of the clutch mechanism to the other. Alternatively, in a recording apparatus that transmits a driving force of a pulse motor to a second driving system that is interlocked with a third gear, when a clutch is switched by the clutch mechanism,
Control means is provided for interrupting the holding excitation of the pulse motor in the drive stop state, and for performing the switching operation by moving the first gear of the clutch mechanism in a state of being engaged with the drive gear during the interruption period. Since the configuration is adopted, the transmission switching mechanism is not subjected to excessive force by the holding excitation torque of the pulse motor, so that the clutch can be reliably switched, and there is an excellent effect that no malfunction occurs.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control system of a recording apparatus employing the present invention, and FIG. 2 (A) is a timing chart showing changes in drive voltages of a feed motor and a clutch solenoid in the configuration of FIG. FIG. 2B is a flowchart showing the control procedure of the MPU shown in FIG. 1, FIG. 3 is a top view showing the configuration of the main part of the recording apparatus common to the conventional configuration and the present invention, and FIG. FIG. 5 is an exploded perspective view of the clutch mechanism of FIG. 5, and FIG. 5 is a sectional view of the clutch mechanism of FIG. 1 ... platen, 5 ... carrier 11 ... feed motor 13 ... clutch solenoid 12 ... clutch, 12a ... clutch body 14 ... lever, 16 ... clutch pulley 20 ... clutch gear 21 ... clutch spring 24 …… MPU, 25… ROM 26 …… RAM, 27 …… Timer

Claims (2)

(57) [Claims] A first gear of a clutch mechanism is meshed with a drive gear for transmitting a driving force of a pulse motor, and when the clutch is switched, the first gear is moved while meshing with the drive gear. The engagement is switched from one of the second gear and the third gear of the clutch mechanism to the other, and
A driving device for transmitting a driving force of a pulse motor to a first driving system interlocked with a third gear or a second driving system interlocked with a third gear; Control means for interrupting the holding excitation of the pulse motor, and performing a switching operation by moving the first gear of the clutch mechanism in a state of being engaged with the drive gear during the interruption period. Recording device. 2. The method according to claim 1, wherein the control means stores an excitation phase of the pulse motor before the shut-off period in a storage means, and controls the excitation phase after the cut-off period to be equal to the excitation phase stored in the storage means. The recording apparatus according to claim 1, wherein: