JPS6242794B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording apparatus, and more particularly to a recording apparatus in which a carriage driving means is improved and the structure is simplified.

Generally, a recording device (printer) used as an output device for a computer or the like is configured to print using a print head mounted thereon while moving a carriage parallel to a platen.

1 and 2 explain the structure of a conventional printer of this type. In the figures, the printer, designated as a whole by reference numeral 1, has left and right side plates 2, 3,
Guide shafts 4 and 5 are horizontally suspended between the two, and a carriage 6 is slidably mounted astride both. A timing belt 7 is arranged parallel to the two guide shafts 4 and 5. One end of the timing belt 7 is connected to a pulley 9 rotatably supported on a bracket 8 fixed to the outer surface of the right side plate 3, and the other end is connected to the output shaft of a motor 10 fixed to the outer side of the left side plate 2. The timing belt is hung on an integral pulley 11, and the carriage 6 is fixed to a part of this timing belt.
It moves left and right as the timing belt runs. On the other hand, there is a slit plate 12 between the left and right side plates 2 and 3.
is horizontally suspended parallel to the guide shafts 4 and 5, with the slit plate 12 in between, a light emitting element is provided on one side, and a light receiving element 13 is provided integrally with the carriage 6 on the other side. The light receiving element is detected by the light beam passing through the many slits 12 formed in the plate 12.
By turning it on and off, the position of the carriage was detected and a print timing signal was obtained.

However, when such a structure is adopted, the carriage runs through an intermediate member called a timing belt, which is run by a drive source separate from the carriage, so the position may change due to expansion and contraction of the timing belt or changes over time. A deviation occurred, making it impossible to detect an accurate position or obtain an accurate timing signal.

Therefore, there are devices in which a light-emitting element and a light-receiving element are mounted on a carriage to detect the position of the carriage. With this configuration, it is certainly possible to obtain accurate timing signals. however,
In this configuration, the pitch of the slits 12a of the slit plate 12 becomes the minimum movement pitch of the carriage, and it has been difficult to make the minimum movement pitch of the carriage sufficiently small due to problems in manufacturing the slit plate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a recording device with a simple configuration that can detect the position of a carriage with a pitch smaller than the array pitch of the detected parts of the position detection means, and can perform the detection extremely accurately. be.

Hereinafter, details of the present invention will be explained in conjunction with embodiments shown in the drawings.

FIG. 3 and subsequent drawings are for explaining one embodiment of the present invention. In the drawings, a pair of guide shafts are provided horizontally and in parallel between the left and right side plates 21 and 22 of the printer, which are generally designated by the reference numeral 20. 23 and 24 are suspended horizontally, and one of the guide shafts 23 has a rack gear 23a formed on its side surface over almost its entire length. A carriage 25 is slidably fitted into these two guide shafts 23 and 24 and moves along these shafts.

The carriage 25 is provided with a print head 26 and a motor 27, and on both sides of the carriage 25 are sensors 28, 29 made of magnetic induction elements, etc.
is provided and faces the rack gear 23a.

As shown enlarged in FIGS. 5 and 6, the carriage 25 has a pinion gear 30 fixed to the output shaft of the motor 27, which is rotated by the motor 27, inside the carriage 25. 30 meshes with the rack gear 23a. Therefore, when the motor 27 rotates, the pinion gear 30 rotates and meshes with the rack gear 23a of the fixedly disposed guide shaft 23, so that the entire carriage 25 is moved left and right. As is clear from FIGS. 4 and 6, the carriage 25 moves by dragging one end of a lead wire 31 that supplies driving current and detection signals from the sensors 28 and 29 to the outside.

A guide shaft 23 is provided between the left and right side plates 21 and 22,
A platen 32 is rotatably mounted horizontally in parallel with the printing head 24 and facing the printing head 26 of the carriage 25. A gear 33 is fixed to the outer end of the rotating shaft of the platen 32, and this gear 33 meshes with a gear 35 fixed to the output shaft of the motor 3 fixed to the inside of the side plate 22. 34
When the platen 3 rotates, the platen 3
2 rotates and feeds the printing paper (not shown).

In addition, what is indicated by the reference numeral 36 in FIG. 5 is an ink ribbon.

Next, the operation of this embodiment configured as above will be explained.

A movement command is input from a control device (not shown) to the motor 27 provided on the carriage 25, and when the motor 27 rotates, the pinion gear 30 rotates and is engaged with the rack gear 23a, so the carriage 25 moves in either the left or right direction. is sent to the specified pitch.

At this time, sensors 28 and 29 made of magnetic induction elements fixed to the carriage 25 are facing the rack gear 23a, and since the sensors 28 and 29 are facing the peaks and valleys (or valleys and peaks) of the rack gear 23a, The induced voltage varies depending on the pitch of the rack gear, and output signals as shown at 28a and 29a in FIG. 7 are obtained.

In this way, the sensors 28 and 29 have different detection timings for the rack gear 23a.

These output signals 28a, 29a are shaped by a waveform shaper (not shown), and are shown in FIG.
As shown in 9b, a rectangular wave is obtained, and based on these waveform-shaped rectangular waves 28b and 29b, the seventh
A print timing signal indicated by reference numeral 37 in the figure is obtained.

As is clear from FIG. 7, a large number of printing timing signals are obtained from one tooth of the rack gear 23a.

Then, according to this print timing signal 37, a print signal is input to the print head 26 in response to a print command from the control circuit, and a predetermined print operation is performed.

Since the rack gear 23a can be formed accurately mechanically, the obtained signal is
If even 9 is accurate, it will be an extremely accurate signal, and the accurate position of the carriage 25 can be detected, and an accurate timing signal can be obtained. Furthermore, the position of the carriage can be detected with a pitch smaller than that of the teeth of the rack gear 23a.

In addition, in the above explanation, the sensors 28, 29
Although a magnetic induction element is used as a position detection means and a rack gear 23a is provided opposite the magnetic induction element, the position detection means facing the sensors 28 and 29 is not limited to the rack gear 23a, but may also be a mark arranged at an accurate pitch. If there are any marks, any marks may be used, and the sensors 28 and 29 can be freely selected to be capable of detecting these marks, such as magnetically sensitive sensors.

Further, the carriage 25 is connected to a motor 27 which is a driving source.
Unlike devices that use intermediate drive force transmission means such as timing belts, its operation is extremely accurate and the structure can be simplified.

As is clear from the above description, according to the present invention, in a recording device equipped with a carriage that mounts a recording head and moves left and right, a motor provided on the carriage, and a motor that is rotationally driven by the motor, rotate the carriage. a rotating means for moving the carriage, a position detecting means having detected parts arranged at predetermined pitches along the moving direction of the carriage, and a first position detecting means provided on the carriage for detecting the detected part of the position detecting means. and a second sensor means that is provided on the carriage and detects the detected portion of the position detection means at a timing different from that of the first sensor means; Based on the detection result, the position of the carriage is detected at a pitch finer than the pitch of the non-detected parts of the position detecting means, so that the position of the carriage is smaller than the pitch of the detected parts of the position detecting means. A recording device capable of detecting the position of a carriage and performing the detection extremely accurately can be achieved with a simple configuration.

[Brief explanation of the drawing]

FIGS. 1 and 2 are a plan view and a side view explaining a conventional structure, FIG. Fig. 5 is a partially enlarged longitudinal sectional side view of the carriage, Fig. 6 is a partially longitudinal sectional front view of the carriage, and Fig. 7 is a timing chart explaining a method for obtaining a timing signal based on a detection signal by a sensor. It is. 20...Printer, 21, 22...Side plate, 2
3, 24... Guide shaft, 23a... Rack gear, 2
5...Carriage, 26...Print head, 27...
...Motor, 28, 29...Sensor, 30...Pinion gear, 32...Platen.

Claims (1)

[Scope of Claims] 1. A recording device equipped with a carriage that carries a recording head and moves left and right, comprising: a motor provided on the carriage; and a pinion that is rotationally driven by the motor and moves the carriage by its rotation. a fixed rack provided with teeth at predetermined pitches along the direction of movement of the carriage and meshing with the pinion gear; and first sensor means provided on the carriage for detecting the teeth of the rack. and a second sensor means provided on the carriage for detecting the teeth of the rack at a timing different from that of the first sensor means, and detecting the teeth of the rack based on the detection results of the first and second sensor means. A recording device characterized in that the position of the carriage is detected at a pitch finer than the pitch of the teeth of the carriage.