JPH10832A - Impact serial printer device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent troubles such as a breakage of the printing head, a jamming of paper or an unfavorable running of the paper from generating. SOLUTION: The thickness of a paper 5 is detected by a sensor and counted, and when the counted value is larger when being compared with a reference value which has been stored, an alarming is indicated, and at the same time, the printer is placed under an unprintable state. The rotation of a motor 13 is transmitted to a shaft 3 by a power transmission mechanism. On a carriage which is eccentrically fitted on the shaft 3, an automatic gap adjusting arm 7 is integrally formed, and also, a printing head 1 is loaded. A plurality of slits 15a with uniform angular intervals and a single part 15b without slit, which a slit wheel 15 being provided in the power transmission mechanism owns, are detected by a photosensor 16 at the time of both normal and reverse rotations of the motor 13. A control circuit of the printer places the printer under a printing possible state or an unprintable state depending on the amount of the pulse signal number of the part 15b without slit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impact serial printer, and more particularly to an impact serial printer capable of using continuous copying paper.

[0002]

2. Description of the Related Art An impact serial printer is advantageous in that it can also print copy paper, but the number of copies and the thickness that can be used differ depending on the model of the printer.

Whether or not the number of copies and thickness can be used is described in a manual such as an instruction manual, but actually, it depends on a judgment based on the experience of the user who uses the printer. I had no choice.

[0004] In an impact printer, a print control method for making the print stroke constant by increasing or decreasing the distance between the platen and the printing unit according to the thickness of the print medium, and obtaining uniform and good print quality is known. , JP 57
No. 110475.

[0005]

In the above conventional method,
In many cases, they do not read manuals such as instruction manuals, or even if they do, they do not understand or do not refer to them. As a result, the user tends to use a large number of sheets or a thick sheet outside the usable specification. When a large number or thick paper of a nonstandard size is used, troubles such as breakage of the print head, paper jam, or poor paper running are likely to occur.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an impact serial printer which can prevent such troubles as breakage of the print head, paper jam or paper running failure.

[0007]

The present invention employs the following means to solve the above-mentioned problems.

(1) An automatic gap adjusting mechanism between the print head and the paper is provided, the thickness of the paper is detected and counted by a sensor, and when the counted value is larger than a previously stored reference value, An impact serial printer that displays a warning and disables printing.

(2) The impact serial printer according to (1), wherein the print head is mounted on a carriage, and an arm formed integrally with the carriage contacts and separates from the sheet.

(3) The impact serial printer according to (2), wherein the carriage is moved by an eccentrically engaged shaft gear and shaft.

(4) A slit wheel is provided as an element of a power transmission mechanism for moving the carriage, and when the slit wheel rotates, the sensor is provided with a plurality of slits having a uniform angular interval provided by the slit wheel and a single slit. The impact serial printer according to (2), wherein the impact serial printer detects a portion without a slit.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic view of an impact serial printer which is the basis of the present invention.

A print head 1 and an ink ribbon cartridge 2 are mounted on a carriage 6 which moves left and right while being guided by a shaft 3. The print head 1 includes an ink ribbon cartridge 2 on a sheet 5 wound around a platen 4.
Prints with impact of the ink. The gap between the print head 1 and the surface of the sheet 5 is a constant value for sheets of various thicknesses.
It is desirable that printing be performed.

FIGS. 2A to 2C are views showing the operation of the print head 1 in the gap direction with the surface of the paper 5.

In order to move the carriage 6 on which the print head 1 is mounted back and forth in the direction of the paper 5, the shaft gear center 14b of the shaft gear 8 is shifted (eccentric) with respect to the shaft center 14a of the shaft 3. In this state, the shaft 3 and the shaft gear 8 are fixed. FIG. 2 (A)
(The shaft center 14a is almost directly above the shaft gear center 14b), the carriage 6 moves in the front-rear direction with respect to the paper 5 when the shaft 3 rotates forward and backward around the shaft gear center 14b. , But hardly moves up and down. The rotation of the shaft 3 and the shaft gear 8 is the same as that of the motor gear 1
2. The transmission is performed by transmitting the torque limit gear 11, the idle gear 10, and the driven gear 9.

Next, the automatic gap adjusting mechanism will be described. In FIG. 2A, the motor 13 is connected to the print head 1.
3A, the automatic gap adjusting arm (hereinafter, referred to as the “AGA arm”) 7 which is a portion protruding from the carriage 6 comes into contact with the surface of the paper 5 in a short time. become. The torque limit gear 11 shown in FIG. 2 (C) has a structure as shown in FIG. 3 (B).
b) above. That is, the torque of the motor gear 12 (tentatively Ta) becomes the torque of Tb via the A gear 11a, the clutch portion 11c, and the B gear 11b, and is transmitted to the idle gear 10 (of course, Ta> Tb, Tb
= Constant). Therefore, the rotational torque of the shaft 3 is also substantially constant. Therefore, the motor 13 is further moved from the state of FIG.
When the AGA arm 7 continues to rotate in the same direction as the above, the AGA arm 7 presses the surface of the paper 5, so that the torque limit gear 11
The clutch portion 11c slides out, and the rotation of the shaft 3 stops (the motor 13, the motor gear 12, and the A gear 11).
a). In this state, the rotation of the motor 13 is stopped. Next, as shown in FIG. 3C, the motor 13 is rotated in a direction opposite to the above by a specified number of steps. The number of steps is a value for making a constant gap between the print head 1 and the surface of the paper 5. Therefore, even when sheets of various thicknesses are set, the gap between the surface of the sheet 5 and the print head 1 can be set to a constant value.

FIG. 4 is a plan view showing the embodiment described above. A slit wheel 15 is fixed to the driven gear 9 and rotates in synchronization with the driven gear 9. The slit wheel 15 is provided with a plurality of slits 15a having the same width (same angle) at a uniform angular interval as shown in FIG. 4, and a portion 15b having no slit is provided at one position. Slit wheel 15
Is rotated, the slit 15a and the portion 1 having no slit
5b are alternately detected by the photo sensor 16 and output from the photo sensor 16 as a signal. Since the position of the portion 15b having no slit serves as a reference, it is desirable that the driven gear 9 and the shaft gear 8 mesh at a fixed position.

Here, the sheet thickness determining operation will be described below. First, consider a case where a sheet is not set on the platen 4. When the AGA arm 7 rotates the motor 13 in a direction away from the platen 4 as shown in FIG. 5A, a signal as shown in FIG. In FIG. 5C, High is the slit 15a, and Lo of a is
The portion where w is long is the portion 15b having no slit. After detecting several pulse signals from the section a, the rotation of the motor 13 is temporarily stopped. Next, the motor 13 is rotated in a direction in which the AGA arm 7 approaches the platen 4 (see FIG. 5B).
Then, as shown in FIG. 5 (D), after the n-pulse signal is output from the portion a, the output does not change (portion b). This state is a position where the AGA arm 7 is pressed against the platen 4. The above n is a value unique to the printer device, and there is a difference between the devices. Next, the case where the maximum thickness paper within the standard is set on the platen 4 is considered. FIG. 3 (A) and FIG.
In (C), if paper 5 is the maximum thickness paper within the standard,
In the direction in which the AGA arm 7 moves away from the sheet 5, a signal similar to that shown in FIG. The direction in which the AGA arm 7 approaches the platen 4 is the same as described above with reference to FIG.
Is output, and the number of pulses from section a is m. Here, as compared with n described above, n> m, and nm is a value representing the thickness of the maximum thickness paper within the standard. This nm (provisionally referred to as p) does not differ depending on the printer device, and is a substantially fixed value. Therefore p + Δp
The value of (Δp is a margin obtained from an experimental result) is stored in the RAM of the configuration diagram shown in FIG. 7 in advance. Further, the value n, which is unique to the printer device, is stored when the device is adjusted. Now, when the paper thickness is within the standard when the printer is used, the number of pulses (s shown in FIG. 8) until the AGA arm 7 presses the paper 5 is n>s> m, and n
-S <nm, that is, ns <p. Similarly, in the case of non-standard thick paper, the number of pulses (t shown in FIG. 9) is n> m.
> T, and nt> nm, that is, nt> p.
The above ns or nt is calculated by the control circuit, and p +
Compare with Δp. When non-standard paper is used, nt>
Even if p, a normal operation is performed if n−t ≦ p + Δp, as compared with the value p + Δp including the margin.
The printer is ready for use. Conversely, if nt> p + Δp, the control circuit of the printer determines that the printer cannot be used, disables the printer, and displays a warning as shown in FIG. Is displayed.

[0020]

As described above, according to the present invention, when a user sets a thick paper that is out of specification, a warning is displayed and printing is disabled so that the print head is damaged, the paper jam occurs, or the paper is jammed. This has the effect of reducing the occurrence of obstacles such as poor running.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of an embodiment of the present invention.

FIGS. 2A and 2B are a side view and a partial cross-sectional view of an embodiment of the present invention, wherein FIG.
(B) is a cross-sectional view of the shaft and the shaft gear,
(C) is a side view showing a power transmission mechanism from the motor to the carriage.

FIGS. 3A and 3B are a side view and a partial cross-sectional view of one embodiment of the present invention, wherein FIG. 3A is a side view showing a state where an AGA arm is pressed against a sheet, and FIG. FIG. 3C is a side view showing a state where the AGA arm is separated from the sheet.

FIG. 4 is a plan view of one embodiment of the present invention.

FIGS. 5A and 5B are a side view and a signal diagram illustrating an operation of the carriage according to the embodiment of the present invention. FIG. 5A is a side view illustrating a state in which the AGA arm is separated from the platen when no sheet is present. B) AGA when paper is not present
Side view showing the state where the arm is pressed against the platen,
(C) is a signal diagram in the state of (A), and (D) is a signal diagram in the state of (B).

FIG. 6 is a signal diagram in the case where the maximum thickness paper within the standard is used in the embodiment of the present invention.

FIG. 7 is a block diagram of one embodiment of the present invention.

FIG. 8 is a signal diagram in the case where non-standard non-maximum thickness paper is used in the embodiment of the present invention.

FIG. 9 is a signal diagram when non-standard thick paper is used in the embodiment of the present invention.

FIG. 10 is a front view of a main part of a display unit of the operation panel according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 print head 2 ink ribbon cartridge 3 shaft 4 platen 5 paper 6 carriage 7 automatic gap adjusting arm (AGA arm) 8 shaft gear 9 driven gear 10 idle gear 11 torque limit gear 12 motor gear 13 motor 14a shaft center 14b shaft gear center 15 slit wheel 15a Slit 15b Part without slit 16 Photosensor 17 Operation panel 17a Display

Claims (4)

[Claims] An automatic gap adjusting mechanism between a print head and a sheet is provided, and the thickness of the sheet is detected and counted by a sensor.
An impact serial printer that displays a warning and disables printing when the count value is greater than a stored reference value. 2. The impact serial printer according to claim 1, wherein the print head is mounted on a carriage, and an arm formed integrally with the carriage comes into contact with and separates from the sheet. 3. The impact serial printer device according to claim 2, wherein the carriage is moved by an eccentrically engaged shaft gear and shaft. 4. A slit wheel is provided as an element of a power transmission mechanism for moving the carriage, and when the slit wheel rotates, the sensor detects a plurality of slits having a uniform angular interval and a single slit provided by the slit wheel. 3. The impact serial printer device according to claim 2, wherein a portion having no image is detected.