JPS61279576A - Electronic typewriter - Google Patents

Abstract

PURPOSE:To enable a runaway due to an abnormal operation to be prevented by sending a stopping signal to each driving means, by providing operation- detecting means for a carriage, a wheel, a ribbon and a platen, and a logical means for generating an operation-stopping command signal in correspondence with an abnormal operation detected. CONSTITUTION:When the carriage 4 is stopped for the reason of the presence of foreign matter in a passage for a carriage or for other reason during driving of the carriage, a time-over signal (f) is outputted from a timer means 32 after a predetermined lapse of time and an accord signal (e) is not outputted from a comparing means 31, so that an operation error signal is inputted from an AND circuit 35 to an input terminal 19a of an OR circuit 19. When the carriage is moved for the reason of overrun or the like in the presence of a carriage stopping command, an operation error signal is inputted to the second input terminal 19b of the OR circuit 19 from an AND circuit 36 which has input terminals supplied respectively with a stopping command signal (a) from an OR circuit 33 and a pulse signal from a wave-shaping circuit 28.

Description

[Detailed description of the invention] Industrial applications The present invention relates to electronic typewriters.

Conventional technology Electronic typewriters perform printing operations by repeatedly driving and stopping the carriage, printing wheel, etc. at predetermined timings, but if there is some abnormality in the mechanism and the operation is not performed correctly, the conventional operation detection method Those without the means would issue the next action execution command without taking any action.

Problems to be Solved by the Invention However, in the conventional system, the operation continues even after the abnormal operation, and, for example, printing continues with the print wheel positioning deviated. Therefore, an object of the present invention is to detect the occurrence of an abnormal operation and prohibit the subsequent operation, thereby minimizing the abnormal operation.

Means for Solving the Problems In order to solve the above-mentioned problems, the electronic typewriter of the present invention includes operation detection means for each of the carriage, wheel, ribbon, and platen, and an operation stop command in response to an abnormality detected therein. The device is characterized in that it includes logic means for generating a signal.

Effect of the present invention The operation control device receives mechanism abnormality information detected by the carriage movement detection means, the wheel rotation detection means, the ribbon winding detection means, or the platen rotation detection means, and sends a stop signal to each drive means, This makes it possible to prevent runaways caused by abnormal operations.

Embodiment FIG. 1 is a block diagram of an electronic typewriter in an embodiment of the present invention. First, the basic operation will be explained. A key code corresponding to a key pressed on the keyboard 1a constituting the input means 1 of the electronic typewriter is sent to the operation control device 2.

The operation control device 2 is composed of a microcomputer, and controls operations such as printing, erasing, carriage movement, line feed, etc. based on the key code received from the input means 1.

In the case of a printing operation, an instruction is given to the printing wheel driving means 6 to rotate the printing wheel so that the characters to be printed are in front of the hammer 16, and a pulse constantly fed back is read by the printing wheel rotation detection means 8. When the target position is reached, a stop command is issued to the print wheel drive means 6, and then current is applied to the hammer drive means 16, which is the nlenoid, for a certain period of time, so that the hammer 16 strikes the type on the print wheel γ and prints. Characters are printed by striking the paper wound around the platen 13 via the ribbon 10.

After printing, in order to wind up the used printing ribbon, the ribbon driving means 9 is given a printing ribbon selection and driving instruction to wind up the printing ribbon 1°, and after receiving a winding completion signal from the ribbon winding detection means 11, the ribbon is driven. The means 9 is stopped.

Similarly, when moving the carriage or changing the movement, the carriage 4 or the platen 13 is moved to the carriage 4 or the drive means 3. Carriage movement detecting means 6. Driven by platen driving means 12. The completion of the operation is detected by the platen rotation detection means 14, and the carriage drive means 6. Control is performed to stop the platen driving means 12.

The main operating errors of electronic typewriters are listed below.

(1) 0 when the carriage stopped while driving the carriage
(2) The carriage moved during a carriage stop command.

(3) The print wheel stopped while it was being driven.

(4) The print wheel rotated during the print wheel stop command.

(6) While the ribbon is being driven, the ribbon winding is not completed even after a certain period of time.

(6) While driving the platen, the rotation of the platen by a certain amount is not completed even after a certain period of time.

The present invention notifies the user with an alarm when these operational errors occur, and also causes the mechanism to stop.

Next, taking as an example the operation errors (1) and (2) above, that is, the carriage operation error, the process from detection of the operation error to generation of the mechanism stop command will be described in detail with reference to the carriage control block diagram shown in FIG. 2.

When a carriage feed command (for example, a tab movement command) is sent from the input means 1 to the operation control unit 2, the carriage control unit 20 in the operation control unit 2 first sends a start command to the motor drive device 21 to either the left or right direction. A direction instruction indicating whether to move is output. Thereby, the motor drive device 21 drives the motor 22 and rotates the gear 23 attached to the shaft of the motor 22. The timing belt 2 is placed between the gear 23 and the gear 25 provided on the opposite side.
8, the carriage 4 attached to the timing belt 26 is moved. The movement of carriage 4 is controlled by gear 23.
Feedback is provided by the carriage movement detecting means 5, which includes a multi-pole (for example, 48-pole) magnetized magnet 24 and an MR element 27 provided opposite the magnet 24. The output from the MR element 27 is obtained by converting changes in magnetic flux from the magnet rotating together with the gear 23 into an electrical signal, and can be said to be approximately a sine wave. This signal is input to the waveform shaping circuit 28, converted into a rectangular wave, and sent to the pulse counting means 29.
The number of pulses corresponding to the moving distance of the carriage 4 is counted. On the other hand, when the carriage control unit 2o outputs a start signal to the motor drive device 21, the register 30
The number of pulses by which the carriage 4 should move is set in , and the comparing means 31 constantly compares the contents of the register 30 and the pulse counting means 29 . Carriage 4
When the pulse count reaches the target position, the contents of the register 30 and the pulse count means 29 match, so that the comparison means 31 outputs a match signal. This match signal is output from the OR circuit 33. O
The stop command is input to the motor drive device 21 through the entire R circuit 37, and the carriage 4 is stopped. The other input terminal of the OR circuit 33 is configured to receive a stop command from the carriage control section 2o, so that the carriage control section 20 can forcibly stop the carriage 4. Further, the output of the OR circuit 33 is connected to a first input terminal of an AND circuit 36 via an inverter 34. A second input terminal of the AND circuit 35 is connected to a time-over output of a timer means 32, which is set to a predetermined value by the carriage control section 2o at the start of motor drive. In other words, when the carriage 4
When the timer means 32 stops, a predetermined time has elapsed and a time over signal is output from the timer means 32, and the comparison means 31
Since no coincidence signal is output from the AND circuit 36, the operation error signal is sent to one input terminal 1 of the OR circuit 19.
9a.

Additionally, when the carriage moves due to overrun or other reasons during a carriage stop command, an operation error signal is generated by an AND circuit 36 whose input terminals are connected to the stop command signal from the OR circuit 33 and the pulse signal from the waveform shaping circuit 28. is OR
It is input to the second input terminal 19b of the circuit 19. The other input terminals of the OR circuit 19 receive a detection signal 19a indicating that the printing wheel has stopped during driving from the printing wheel rotation detection means 8 and a detection signal 19d indicating that the printing wheel has moved during the command to stop the printing wheel from the ribbon winding detection means 11. A detection signal 19θ indicating that the ribbon has stopped during driving is detected by the platen rotation detection means 14 as a detection signal 1s indicating that the ribbon has stopped during driving.
t are respectively input.

Print wheel rotation detection, ribbon winding detection, and platen rotation detection can also be realized by the same method as carriage movement detection. Note that since fine pitch control such as carriage control is not required for ribbon winding and platen rotation, these operation detection means 11.
14 is 0N1 using a magnet and a Hall element or a protrusion on the cam so that one pulse signal is generated with one rotation of the cam.
One of the outputs of the QOR circuit 19, which can be configured with a microswitch that is turned OFF, is input to the buzzer driving means 17 to sound the buzzer 1st. On the other hand, the OR circuit 19 serves as an operation stop command generating means, and its output is sent to the carriage stop command terminal 2 of the motor and drive device 21 via the OR circuit 3.
jc as well as a printing wheel stop command,
A ribbon winding stop command, a platen rotation stop command, and a hammer drive stop command are input to the print wheel drive means, ribbon drive means, platen drive means, and hammer drive means, respectively, to stop the mechanisms.

Although six types of operational errors have been given here, an error in detecting the initial position of the carriage 4 or print wheel 7 when the power is turned on may also be considered.

Effects of the Invention As described above, the present invention is capable of minimizing abnormal operation when an operation error occurs in an electronic typewriter by providing an operation error detection means and an operation stop command generation means.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an electronic typewriter according to an embodiment of the present invention, and FIG. 2 is a block diagram mainly showing a carriage control section in this embodiment. ... Carriage movement detection means, 8 ... Print wheel rotation detection means, 11 ... Ribbon winding detection means, 14 ...
. . . Platen rotation detection means, 19 . . . Operation stop command generation means. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Illustration 2

Claims (1)

[Claims] Carriage, printing wheel, printing ribbon/erasing ribbon,
Logic that generates an operation stop command when an operation error is detected in any one of the carriage movement detection means, print wheel rotation detection means, ribbon winding detection means, and platen rotation detection means that detect each movement of the platen. An electronic typewriter characterized by comprising means.