JPS61175069A - Output unit - Google Patents

Abstract

PURPOSE:To enable only one sensor to function two kinds of sensing functions by providing a means of judging the first detection and the second detection on the basis of the waveform of output signals from a single position detector to perform the first detection for vertical moving positions of the output portion of a printing ribbon cassette and the second detection for given position of the carriage. CONSTITUTION:Under the condition that a ribbon cassette 7 is lifted, a sensor arm 26 goes into an aperture 27a, and thereby the internal phototransistor of a sensor 27 goes OFF. On the contrary, when the cassette 7 is lowered, the arm 26 turns in the opposite direction and comes out of the aperture 27a of the sensor 27, and thereby the internal photo transistor of the sensor again goes ON, permitting the vertical condition of the cassette 7 to be discriminated. When the carriage 2 moves in the direction of X on a guide rail 8 and the position arm 28 enters the aperture 27a of the sensor 27 in the carriage 2, the photo transistor 27c in the sensor 27 is turned OFF, and it is detected that the carriage 2 is restored to the home position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an output device that performs printing, such as an electronic typewriter or an output section of a computer system, and particularly relates to an output device that detects the position of a carriage or a printing ribbon.

[Prior Art] An output device that performs printing, such as an electronic typewriter or an output unit of a computer system, generally has a carriage that reciprocates with respect to printing paper. In controlling the reciprocating movement of the carriage, it is important to determine the home position at the starting point of the reciprocating movement of the carriage, that is, at the left end when viewed from the operating side. Therefore, this type of conventional device is equipped with at least one dedicated sensor for detecting whether the carriage is in the home position.

Additionally, a printing ribbon for printing, an erasing ribbon for erasing, etc. are mounted on the carriage.6 Normally, this printing ribbon is placed on the printing paper on which the device user (operator) is currently printing characters. position below the printing line so that it can be seen visually. Then, when transferring characters to printing paper, this printing ribbon is shifted to the height of the printing line.

On the other hand, the erasing ribbon is located, for example, below the printing ribbon and parallel to the printing ribbon, and when erasing printing, the erasing ribbon is shifted to the height of the printing line currently being printed.

Therefore, in order to control the series of printing and erasing operations described above, it is necessary to determine the vertical movement position (shift position) of the ribbon at that time.
It is necessary to detect this, and therefore, at least one sensor dedicated to this detection must be provided.

By the way, if one sensor is used as both the carriage home position sensor and the ribbon cassette vertical position sensor to have two detection functions, that single sensor will serve as both the carriage home position sensor and the ribbon cassette vertical position sensor. It must be possible to determine whether a return to the position is being detected or whether the cassette is being detected moving up or down.

[Objective] The present invention has been made in view of the above-mentioned points, and it is possible to detect the case where a single sensor detects the home position of the carriage and the case where the vertical position movement of the cassette is detected.
By changing the form of the detection signal sent to the output device control section, the output device control section can determine whether it is detecting the former or the latter, thereby ensuring that one sensor can detect two types of signals. The purpose is to provide an output device that can use different detection functions.

In order to achieve such an object, the present invention provides an output device equipped with a carriage that carries an output unit such as a print ribbon cassette and moves back and forth along an output medium, in which the output unit such as the print ribbon cassette is moved in the vertical direction. a single position detecting means that performs a first detection of the moving position of the carriage and a second detection of a predetermined position such as returning the carriage to its home position; The present invention is characterized by comprising a discriminating means for discriminating between the first detection and the second detection.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an example of the overall appearance when the present invention is applied to an electronic typewriter, where 100 is the electronic typewriter and 1 to 7a are its constituent members. First, 1 is the keyboard for character input, 2 is the carriage, and 3 is the carriage 2.
4 is a printing paper fed by the platen 3, 5 is a type wheel mounted on the carriage 2,
Reference numeral 8 denotes a printing hammer unit 7) for selectively striking the type on the type wheel, and 7a represents an ink ribbon interposed between the type wheel 5 and the paper 4.

In the typewriter 100 shown in the figure, input keys including character keys and function keys are arranged on the keyboard 1.
By operating the daisy type type wheel 5, the type provided on the outer periphery is struck from the back side by the printing hammer unit 8, and the type mentioned above is struck onto the printing paper 4 wound on the platen 3 via the ink ribbon 7a. It is engraved to record characters, etc.

FIG. 2 shows a detailed configuration example of the carriage portion of the electronic typewriter shown in FIG. , move in the x' direction (left/right direction).

The upper part of the carriage 2 facing the platen 3 is provided with a type embossing mechanism consisting of a type wheel 5 and a print hammer unit 6. A printing ribbon cassette 7 containing a printing ribbon 7a and extending the printing ribbon 7a over the entire surface of the printing wheel 5 is mounted on the carriage 2 on the operator's side at the rear of the printing mechanism.

7b is a rotating shaft attached to the rear end of the printing ribbon cassette 7 to move the tip of the cassette 7 up and down. One end of the 0-rotating shaft 7b is a carriage board 11'. A bearing mounted on the carriage board 11' is rotated by the plate 7C. Is this rotation axis supported? A gear 24 is fixed to the other end of b, 23 is a gear that meshes with this gear 24 at right angles, and the gear 24,
As 23, for example, a bevel gear or the like can be applied. 25
is a rotating shaft of the gear 23, and a bearing vertically disposed on the carriage base plate 11' is rotatably supported by a plate 25a.

The above-mentioned rotating shaft 25 has an abbreviated plate-shaped sensor arm 2.
One end of 8 is fixed.

Reference numeral 27 denotes a transmission type photointerrupter, which is fixed to the end of the carriage 2 on the home position side on the substrate 11'. The sensor arm 2B is arranged on the right side of the photointerrupter 27 (the right side when viewed from the operator), and blocks the transmitted light of the photointerrupter 27 by rotating.

During the printing operation, the exposed portion of the printing ribbon 7a is rotated in the direction of arrow A by a plunger 15 shown in FIG. It is interposed between the printed characters 5a on the platen 5 and the printing paper 4 on the platen 3. This rotation of the rotating shaft 7b is directly transmitted to the gear 24, and rotates the teeth and the wheel 23 meshed with the gear 24 in the G direction. At the same time, the rotating shaft 25 of this gear 23 also rotates in the direction of the arrow G in the figure, so the tip of the sensor arm 2B mounted on the shaft 25 rotates in the direction of the arrow in the figure, and is inserted into the gap 27a of the photointerrupter, which is a sensor. Get into it.

The photo interrupter 27 is a light emitting element 27 such as an LED.
If there is no light blocking object in this gap 27a, the light emitted from the light emitting element 27b will be transmitted to the light receiving element 2.
7c is incident, and the internal phototransistor is turned on. On the other hand, when there is a light blocking object in the gap 27a, the light from the light emitting element 27b does not enter the light receiving element 27c, so the internal phototransistor is turned off.

Therefore, when the ribbon cassette 7 is raised as described above, the sensor arm 2B enters the gap 27a.
The phototransistor inside the sensor 27 is turned off. Conversely, when the printing ribbon cassette 7 is lowered, the sensor arm 2B rotates in the opposite direction to the arrow F in conjunction with the lowering of the printing ribbon cassette 7, and the sensor arm 2B is removed from the gap 27a of the sensor 27, so that the phototransistor inside the sensor is turned ON again. state. In other words, the phototransistor inside the sensor 27 is turned on.
Alternatively, by detecting the OFF state, the vertical state of the ribbon cassette 7 can be identified.

FIG. 3 shows a detailed example of the internal structure of the carriage 2 on the lower stand 11 exposed by removing the above-mentioned print ribbon cassette 7.

13 is an erasing ribbon, and 12a and 12b are feeding reels and take-up reels for feeding the erasing ribbon 13, which are rotatably supported on the left and right outer sides of the front of the lower stand 11 when viewed from the operator side.

Reference numeral 14 designates a model shift arm that is pivotally supported on both left and right sides of the lower stand 11, and 14a and 14b are guide rollers that are pivotally supported on both left and right ends of the shift arm 14. Erasing ribbon 13 pulled out from reels 12a and 12b
is stretched for the guide rollers 14a and 14b. 15 is a plunger, IB is a gear (pawl wheel), 17 is an arm for stepping the gear, and 18 is a presser spring for preventing reverse rotation.
The rotating shaft of the take-up reel 12b is inserted through a through hole provided in the lower base 11, and a serrated gear 18 is fixed to the tip thereof. The arm 17 is rotatably mounted on the upper part of the lower stand 11,
Every time the plunger 15 moves up and down once, the gear IB
Only the teeth move forward. Due to this walkway, the gear 1B rotates the take-up reel 12b in the direction of the arrow in the figure to remove the erasing ribbon 13.
, and move this ribbon 13 by one character.

The presser spring 18 engages with the serrated gear 1B to prevent the gear IB from reversing, and also functions to stop the peripheral teeth of the gear IB each time it rotates by one tooth.

A ribbon holder 19 is always pressed in the direction of arrow E in the figure by being biased by a coil spring 21 attached to a shaft 20 provided on the lower stand 11.

The pressing force of the ribbon presser 19 prevents the erasing ribbon 13 from becoming loose or sagging, which occurs when the erasing ribbon 13 is fed character by character.

Returning to FIG. 2, reference numeral 28 is a position arm which is placed on the extension of the gap 27a of the sensor 27 and near the left end of the guide rail 8 in order to detect whether or not the carriage 2 has reached the home position. It is located behind the position. The carriage 2 moves in the X direction (left side) on the guide rail 8, and the positioning arm 2
8 enters the gap 27a of this sensor 27 into the carriage 2, the phototransistor 27c inside the sensor 27
OFF I, it is detected that the carriage 2 has returned to the home position. In this way, immediately after the position arm 28 enters the sensor gap 27a, the carriage 2 is moved to the right again by a small amount, and the carriage 2 returns to a predetermined position where the position arm 28 has completely retreated from the sensor gap 27a. Define the position in advance. By such an operation, for example, the electronic typewriter 100 starts printing from the home position, and at this time, the cassette upper and lower sensor arms 2B are in the sensor gap 2? Even if it enters a, position arm 2
8 does not prevent its operation.

FIG. 4 shows an example of the configuration of a circuit for controlling the operation of the electronic typewriter of the present invention having the above-described configuration.

In this figure, 23 is a microprocessor (MPU), which is stored in a ROM (read only memory) 30. A keyboard circuit 31 controls the operation of the entire typewriter device according to a processing procedure (program) as shown in FIG. 7, and has a function of manually operating keys by key operation. The microprocessor 28 controls the keyboard circuit (KEY) 31, RAM (Random Access Memory) 32, ROM 30, and interface circuit 33 via a common data bus 34 and address bus 35.

Input/output of print data is performed via this data bus 34, and address control of transfer data is performed via an address bus 35. 36 is an R/W for specifying data transfer timing.
It is a signal line.

Input information from the keyboard circuit 31 is processed by interrupt. That is, the occurrence of an interrupt due to the depression of a key on the keyboard circuit 31 is notified to the microprocessor 29 through the interrupt signal line 31'. The encoded key press information generated at this time is output from the keyboard circuit 31 to the data bus 34. The microprocessor 28 performs a generally known print control operation such as storing this press information in a buffer of the RAM 32 or outputting it to the outside through the interface circuit 33.

The interface circuit 33 functions as an input/output port for various data, and associates a predetermined address with specific input/output data. A detection circuit 37 including a sensor 27 for detecting the top and bottom of the cassette is shown, and a drive control circuit 38 is shown as an output system of the interface circuit 33. This drive control circuit 38 converts the logic level information output from the interface circuit 33 into an actual drive voltage level of the drive system 38, and provides this voltage level to each operating mechanism of the drive system 38. The drive system 39 includes a carriage drive system, a platen drive system, a hammer drive system, and the like.

Next, a determination means for determining whether the sensor 27 has detected return of the carriage 2 to the home position or vertical movement of the print ribbon cassette 7 will be described.

If a light blocking object enters the gap 27a of the sensor 27, the sensor 2
If the optical path of the light emitting element 7 is blocked, the sensor 2
The phototransistor 27c inside 7 is turned off,
At this time, the detection circuit 37 generates a logic high level signal. On the other hand, when the optical path of the light-emitting element 27b of the sensor 27 is not blocked, the phototransistor 27c inside the sensor 27 is turned on, and the detection circuit 37 generates a low-level logic signal.

First, a case will be described in which the cassette vertical position sensor arm 2B enters the sensor gap 27a.

When a printing command is issued from a state where the printing ribbon cassette 7 is lowered and the printing ribbon cassette 7 is raised, the cassette vertical position sensor arm 2 is activated as described above.
B enters the sensor gap 27a, and as shown in FIG.
Blocks the optical path of 7b. Therefore, as shown by waveform A in FIG. 5, the detection circuit 37 outputs a low level signal before T, but from time T onwards, it outputs a high level signal.

Next, position arm 28 moves to sensor gap 2? A case will be explained in which the case enters a. As shown in FIG. 6, the light emitting element 2 of the sensor 27 is attached to the position arm 28. A vertical hole 40 is placed at the height of the optical path b. Therefore, the fifth
As shown by waveform B in the figure, when the sensor 27 moves and the position arm 28 enters the sensor gap 27a, first, at time 1, the right edge of the position arm 2B becomes the optical path of the light emitting element 27b of the sensor 27. to block As a result, at this time T1, the output of the detection circuit 37 changes from a low level to a high level. Further, when the carriage 2 moves leftward and time T2 comes, the vertical hole 40 of the position arm 28 is located in the optical path of the light emitting element 27b of the sensor 27. At this time, the light from the light emitting element 27b of the sensor 27 enters the light receiving element 27c inside the sensor through the vertical hole 40, and the phototransistor inside the sensor 27 is turned on. Therefore, at this time, the detection circuit 37 outputs a low level signal.

As mentioned above, the position arm 28 is located in the sensor gap 27.
The period from time T when the signal enters point a to time T2 is a high level signal time Ta that the detection circuit 37 outputs. Also,
If the printing ribbon cassette 7 is lowered again while the sensor arm 26 is in the sensor gap 27a, the detection circuit 3
7 outputs a low level signal, but the minimum time until time T5 when the detection circuit 37 outputs a high level signal at a certain time and again outputs a low level signal is Tb. Here, Ta and Tb are set in advance as Ta<Tc, but this condition is based on the vertical movement speed of the printing ribbon cassette 7,
Horizontal movement speed of carriage 2 and position arm 28
This can be easily achieved by adjusting the height of the groove, etc. Here, time 3 is a time immediately after time τ2, and is a time when the vertical hole 40 of the position arm 28 is still located in the optical path of the light emitting element 27b of the sensor 27. Further, it is assumed that the time c from 1 time T to time 3 is shorter than time Tb, and the relationship Ta<Tc<Tb holds.

Vertical position sensor arm 2B or position arm 2
8 enters the sensor gap 27a and the detection circuit 37 at time T1.
After the signal becomes high level, if the signal of the detection circuit 37 is detected at a predetermined time T3 as shown in FIG. 5, which of the arms 28 and 28 has entered the sensor gap 27a. It is judged whether That is, if the arm that entered the sensor gap 27a is the cassette vertical position sensor arm 2G, the detection circuit 37 outputs a high level signal at time T3, and if the arm that entered the sensor gap 27a is the position arm 2B. , the detection circuit 37 outputs a low level signal at time T3. Therefore, the bicycle processor 29 inputs the detection signal of the detection circuit 37 through the interface circuit 33, and as described above, due to the change in this detection signal, the vertical position sensor arm 26 or the position arm 28 closes the sensor gap 27 at time T1.
a, and then at time T3, the level of the output signal from the detection circuit 37 is detected again to detect the return of the carriage 2 to the home position, or to detect the vertical position of the cassette. It is possible to identify whether Now, assuming that the return of carriage 2 to the home position is detected, immediately after this, carriage 2
is returned to a predetermined distance in the outgoing direction (to the right) and located at the home position. At time T4 during this return, the right edge of the position arm 28 again blocks the optical path of the light emitting element 27b of the sensor 27, so the detection circuit 37 generates a high level signal from time T4. After this, at time 〒5.

Now in the positive position, the arm 28 is connected to the light emitting element 27 of the sensor 27.
Since the optical path b is not blocked, the detection circuit 37 generates a low-gibel signal from time T5.

FIG. 7 shows an example of a control procedure when the above-mentioned microprocessor 28 performs the above-mentioned detection operation.

First, in step S50, the detection signal sent from the detection circuit 37 through the interface circuit 33 is compared with a threshold value to determine whether or not the detection signal is a high-level signal. If the judgment is negative, the detection signal is input again and the same judgment process is repeated, and if the judgment is positive, the next step S
For example, if there is a high level signal output from the detection circuit 37 at time TK in FIG. 5, the process moves to step S51 and starts the built-in timer. Proceeding to step S52, it is determined whether the timer has timed up, that is, whether a predetermined time Tc has elapsed since the timer activation. When the timer times up, the process moves to step 353, where the detection signal outputted from the detection circuit 37 through the interface circuit 33 is compared with the threshold value, and if the detection signal of the detection circuit 37' is at a high level, the waveform A in FIG. In this case, the printing operation is performed in step 354. On the other hand, if the detection signal of the detection circuit 37 is at a low level, this is the case of waveform B in FIG. 5, so in step S55 the carriage 2 is moved to the right. Return to the home position.

In this example, a photointerrupter is also used in the sensor to distinguish between the two detection targets based on the difference in the signal width of the detection signal. It does not matter what the criteria for distinguishing signals is.

Further, in this example, the present invention is applied to an electronic typewriter, but the present invention is not limited to this. For example, in an output device such as a computer, detection of the home position of the caliper and the vertical movement position of the ribbon cassette are possible. It goes without saying that the present invention is applicable to any recording device that can use a common sensor for detection.

[Effects] As is clear from the above description, according to the present invention, it is possible to detect that the output unit such as a carriage has returned to a predetermined position such as the home position, and to detect whether the output unit such as a printing cassette is in an upper or lower position. Detection of a movement to a common sensor can be distinguished from the detection of movement by a difference in the waveform such as the amplitude of the detection signal generated by the detection circuit of a common sensor.
This provides the advantage that it is possible to reliably determine which detection target is being detected among the types of detection targets and to perform control operations.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of the external appearance of an electronic typewriter to which the present invention is applied; FIG. 2 is an enlarged perspective view showing the structure of the carriage portion of the electronic typewriter shown in FIG. 1; FIG. FIG. 4 is a block diagram showing an example of the configuration of the control circuit of the electronic typewriter shown in FIG. 1; FIG. 5 is the detection circuit shown in FIG. 4. 6 is an explanatory diagram showing the relationship between the position arm and the sensor in FIG. 2, and FIG. 7 is a flowchart showing an example of the control operation of the microprocessor in the control circuit in FIG. 4. It is. 2... Carriage, 7... Printing ribbon cassette, 7a... Printing ribbon, 13... Erasing ribbon, 15... Plunger, 23.24... Gear, 25... Arm rotation axis, 26... Cassette upper and lower sensor arms, 27... Sensor, 27a... Sensor gap, 28... Position arm. 37...Detection circuit, 38...Drive control circuit, 38...Printing device drive system, 40...Vertical hole. Figure 5 Figure 6

Claims (1)

[Scope of Claims] A carriage that reciprocates along an output medium; an output unit mounted on the carriage and capable of vertical movement for outputting predetermined information to the output medium; a predetermined portion of the carriage; a single detection means for performing a first detection for detecting a position and a second detection for detecting a vertical movement position of the output section, and the first detection according to an output waveform of the detection means; and a discriminating means for discriminating between the second detection and the second detection.