JPS6342879A - Paper bail device for printer - Google Patents

Abstract

PURPOSE:To prevent a printing paper from being wrinkled and enable printing in the vicinity of the top edge of the paper, by providing a paper pressing releasing mechanism for spacing a paper bail from a paper-pressing position on a platen and maintaining the paper bail at the spaced position, and a paper bail returning mechanism for returning the paper bail from the spaced position to the paper-pressing position. CONSTITUTION:When an operating lever 18 is manually operated against an energizing force of a spring 17, a paper bail 4 is spaced from a paper-pressing position on a platen 2. When forked parts of a fastening spring 21 are opened apart from each other against the elasticity thereof by the lever 18 to cause fastening projections 19 to ride over crest parts of fastening parts 21a of the spring 21 and to be engaged with the fastening parts 21a, the paper bail 4 is maintained at the spaced position, so that a printing paper will not be wrin kled due to interference with the paper bail. In addition, a carriage 10 is engaged with and presses an engaging piece 28, whereby a pin 25b is moved toward the platen, and the paper bail 4 is pushed toward the platen by a press ing body 29 and an engaging projected part 30 of an arm 15A to be returned to the paper-pressing position.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a paper holding device for a printer that presses printing paper against a platen surface using a paper bail to perform printing.

(Prior Art) In this type of printer, printing paper fed onto a platen is held down by a paper bail above a printing position where printing is performed by a print head.

(Problem to be Solved by the Invention) In this case, the paper holding portion of the paper bail is moved so as not to interfere with the carriage or print head that is moved left and right.
It was arranged outside the movement range of the print head, and the printing position R and the paper pressing position were arranged vertically apart. Therefore, when printing on the top edge of a printing paper, for example, when printing a postal code or address on the top edge of a postcard, the top edge of the printing paper may not reach the paper bail. In this case, even if paper is fed as the printing of a predetermined print line at the top end of the print paper is completed, the print paper is not sandwiched between the platen and the paper bail, so it may interfere with the paper bail. There was a risk that the printed paper would be wrinkled.

In order to prevent this, conventional methods have been proposed in which printing is not performed until the printing paper reaches the position where it is held down by a paper bail. It was impossible to print near the top edge of the postal code, which caused trouble when printing the postal code as described above.

Structure of the Invention (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention includes a paper holding release mechanism that separates the paper bail from the paper holding position on the platen and holds the paper bail at the separated position; A paper bail return mechanism is provided at one end of the movement range of the carriage and is activated by engagement with a portion of the carriage or print head to return the paper bail from the separated position to the paper holding position.

(Function) Therefore, when printing on the top edge of the printing paper, the paper bail is separated from the paper holding position on the platen by the paper holding release mechanism, and the upper part of the printing position is released, allowing printing on the top edge of the printing paper. There is no interference between the printing paper and the paper bail during the subsequent paper feeding. - After printing on a print line is completed, when the carrier is located at one end of its movement range, the paper bail return mechanism returns the paper bail to the paper holding position on the platen, and the printing paper is placed on the platen. Being held down.

(Example) An example embodying the present invention will be described below with reference to FIGS. 1 to 5.

Now, in the printer of this embodiment, as shown in FIG. 1, the platen 2 is rotatably supported between the left and right sides 91a and 15 of the frame 1 by a shaft portion 2a protruding from both ends thereof, and the outer periphery of the platen 2 is The printing paper 3 is supported in rotation. An operation knob 6 and a feed gear 7 are attached to both left and right ends of the shaft portion 2a of the platen 2.
is manually rotated, or the platen 2 is rotated via a feed gear 7 or the like based on the drive of a paper feed motor (not shown), so that the printing paper 3 on the platen 2 is fed. .

A paper bail 4 is disposed between both side walls 1a and 15 of the frame 10 to press and hold the printing paper 3 in a releasable manner.

A support shaft 8 and a guide rail 9 are installed and supported on both side walls 1a and 1b of the frame 1 so as to extend parallel to the platen 2. A carriage 10 is movably supported on the support shaft 8 and the guide rail 9, and a print head 11 is mounted on the carriage 10.
1a is arranged to face the printing surface of the platen 2 with a predetermined gap, and the carriage 10 has a printing section 11a.
A paper meter 12 is provided to guide the printing paper 3 along the outer surface of the platen 2 when the park is opened.

A ribbon cassette 13 is removably mounted on the frame 1, and a part of the printing ribbon 14 housed therein is exposed to the outside, so that the printing part 11 of the printing head 11
It is arranged in the gap between a and the printing surface of the platen 2. Then, while the carriage 10 is moved along the platen 2 based on the drive of a carriage moving motor (not shown), the printing head 11a prints on the printing paper 3 on the platen 2 through the exposed portion of the printing ribbon 14. It has become.

The paper bail 4 is constructed as follows.

A pair of left and right arms 15A, 15 are provided at both ends of the support shaft 8.
B is rotatably inserted and supported at the base end, and a bar 16 extending parallel to the platen 2 is installed between their free ends. A plurality of pressing rollers 5 are attached to the bar 16 to press down the printing paper 3 on the platen 2, and this pressing is performed. i
It is placed at an upper position that does not obstruct the movement of -111.

The paper bail 4 is located at a paper holding position where the printing paper 3 is pressed against the platen 2 as shown by the two-dot chain line in FIGS. It is designed to be moved and placed in different positions.

The spring 17 urges the paper bail 4 to the paper holding position.

As shown in FIG. 2.3, an operating lever 18 is integrally provided at the upper end of the right arm 15B, and a pair of hemispherical locking protrusions 19 are provided at the intermediate portions on both sides thereof. The cover IC of the frame 1 has a long hole 20 through which the operating lever 18 projects, and a locking spring 21 bent into a bifurcated shape is attached to the back side of the hole 20 with bolts.

A pair of locking portions 21a that engage with both locking protrusions 19 of the operating lever 18 are bent at the middle portion of the locking spring 21. In this embodiment, the operating lever 18, the locking protrusion 19, and the locking spring 21 constitute a paper press release mechanism, and the operating lever 18 is manually operated against the biasing force of the spring 17. As a result, the paper bail 4 is separated from the paper pressing position on the platen 2, and the operating lever 18 opens the two prongs of the locking spring 21 against its elasticity, so that both locking protrusions 19 are moved away from the locking spring. The paper bail 4 is held at the separated position by climbing over the tops of both the locking portions 21a of the paper bail 4 and locking with the locking portions 21a. Also, push the arm 15B toward the platen to open the two prongs of the locking spring 21 against its elasticity (
As a result, the paper bail 4 is returned to the paper pressing position according to the bias of the spring 17.

As shown in Fig. 4.5, a mounting plate 22 is fixed to the left side of the frame l with bolts (not shown), and this mounting plate 22 has two guide holes 23 located on perpendicular lines,
24 is provided transparently. The upper surface of the mounting plate 22 has a link 2
5 is provided by inserting sliding pins 25a and 25b at both ends thereof into both guide holes 23 and 24. A sliding pin 2 inserted into the guide hole 23 on the back side of the mounting plate 22
6 and one sliding pin 25a of the link 25 is fixed to an engagement plate 27, and an engagement piece 28 that engages with the contact piece 10a protruding from a part of the carriage 10 hangs down from a part of the engagement plate 27. has been done. Note that the engagement plate 27 and the link 25 are rotatably connected by a sliding pin 25a. Further, a pressing body 29 is fixed to the other sliding pin 25b of the link 25, which can be engaged with an engaging protrusion 30 provided at the upper end of the left arm 15A of the paper bail 4. In this embodiment, the engagement piece 28, the link 25, the pressing body 29, and the engagement protrusion 30 of the arm 15A constitute a return mechanism for the paper bail 4, and the carriage 10 returning to the home position HP is moved by the engagement piece 28. 28 and is pressed, the link 25 moves from the standby position shown by the solid line in FIG.
, and the pin 25b is moved toward the platen side. Then, the pressing body 29 pushes the paper bail 4 held at the separated position toward the platen to return it to the paper pressing position.

By operating the operating lever 18 to hold the paper bail 4 in the isolated position as described above, the left arm 15
The engagement protrusion 30 of A pushes the pressing body 29 to return the link 25 and the engagement piece 28 from the position indicated by the two-dot chain line in FIG. 4 to the standby position indicated by the solid line.

Incidentally, springs (not shown) may be attached to the link 25 and the engaging piece 28, so that they are normally urged to the standby position.

Now, when printing on the upper end of the printing paper 3 using the printer configured as described above, the carriage 10 is placed at the start side (ps position) of the printing movement range shown in FIG.
By manually operating the operating lever 18, the paper bail 4 is separated from the paper holding position on the printer 2 to open the upper part of the printing position, and both locking protrusions 1 of the operating lever 18 are opened.
9 is locked to both locking portions 21a of the earth mooring spring 21, and the paper bail 4 is held at a separated position. At this time, as shown in FIG. 5, the engaging protrusion 30 of the left arm 15A is placed immediately in front of the pressing body 29 in the standby position.

Next, the platen 2 is rotated by operating the operating knob 6, etc., and the printing paper 3 is set at a printing position where its upper end faces the printing part 11a of the print head 11, as shown by the solid line in FIG. At this time, the upper end of the printing paper 3 is guided by the paper meter 12 along the platen surface.

When the printing of the first print line is completed by the printing operation of the print head 11, the printing paper 3 is moved by a paper feed motor (not shown).
The platen 2 is rotated based on the drive of the platen 2, and the platen 2 is sent to point A shown by the two-dot chain line in FIG.

At this time, the upper end of the printing paper 3 extends tangentially to the platen 2, but since the paper bail 4 is held at a separate position that opens the upper part of the printing position, the printing paper 3 interferes with the paper bail 4. There's nothing to do.

After paper feeding is completed, the carriage 10 is moved to the home position HP side shown in FIG. 1, and when the contact piece 10a of the carriage 10 engages with the engagement piece 28 as shown in FIG. 25 is moved from the standby position shown by the solid line to the operating position shown by the two-dot chain line, and the engaging protrusion 30
9, it is pushed toward the platen 2 side. Therefore, on the right side of the frame 1, the engagement between the locking protrusion 19 of the operating lever 18 and both locking portions 21a of the locking spring 21 is released, and the urging force of the springs 17 of both arms 15A and 15B causes the third ，
In FIG. 5, the paper bail 4 is rotated clockwise, and the paper bail 4 is returned to the paper holding position shown by the two-dot chain line. By this movement of the paper bail 4 returning to the paper holding position, the printing paper 3 is held down at point B on the platen 2. Then, in this state, printing is restarted by operating the print head 11.

As described above, the paper bail 4 can be moved to the paper pressing position with a simple configuration that utilizes the movement of the carriage 10.

(Another Example) Next, another example will be explained based on FIG. 6.7, but the explanation of the same structure as the above embodiment will be omitted.

As shown in FIG. 7, a rotating member 31 is mounted on the frame 1 so as to be located close to the right arm 15B around a support shaft 32 that extends in a direction substantially perpendicular to the axis of the support shaft 8. It is rotatably supported. A pin-shaped actuating member 33 is protrudingly provided on the rotating member 31 so as to be located on the movement trajectory of the carriage 10, and engages with the carriage 10 to rotate the rotating member 31. There is. Between the right arm 15B and the rotating member 31, there is a transmission gear mechanism 3 consisting of a pair of bevel gears 34 and 35 that mesh with each other.
6 is provided, and the rotation of the rotation member 31 is controlled by the right arm 15.
It is designed to be transmitted to B. In this other example, a rotating member 31 having an operating member 33, a transmission gear mechanism 36
, the locking protrusion 19 and the locking spring 21 constitute a paper press release mechanism.

In this alternative example, a well-known automatic paper feeder (not shown), which feeds one sheet at a time from a large number of printing sheets 3 preferably piled up one by one using a friction roller or the like, is attached to the printer and used. When a "paper feed" command signal is output to the printer from a host computer, etc., the carriage 10 is moved to the right end position of its movement range before the printing paper 3 is fed from the automatic paper feeder, and the carriage 10 is moved to the right end position of its movement range. 1o is the operating member 33
The rotating member 31 is rotated counterclockwise in FIG.
, 15B are rotated clockwise in Fig. 6.7, the paper bail 4 is moved from the paper holding position shown by the solid line in Fig. 7 to the separated position shown by the two-dot chain line, and the upper part of the printing position is opened. be done. At this time, as shown in FIG. 2.3, both locking protrusions 19 of the operating lever 18 are locked with both locking portions 21a of the locking spring 21, and the paper bail 4 is held at the separated position.

Next, the friction roller of the automatic paper feeder is driven to send out only one sheet of printing paper 3 toward the platen 2, and then the platen driving motor is driven to print the upper edge of the printing paper. The printer is set in the apparatus, and the first print line is printed by the printing operation of the print head 11. Thereafter, after the first line feed, the carriage 10 is moved to the home position HP, thereby moving the paper bail 4 to the paper pressing position, as in the previous embodiment.

Therefore, in this other example, the release/return operation of the paper bail 4 accompanying the paper feeding operation can be automated.

Effects of the Invention As detailed above, according to the present invention, it is possible to prevent wrinkles on the printing paper by avoiding interference between the printing paper and the paper bail at the end of paper feeding following printing on the upper end of the printing paper. As a result, there is an excellent effect that printing can be performed near the top edge of the printing paper.

[Brief explanation of drawings]

Fig. 1 is a plan view showing almost the entire printer embodying the present invention, Fig. 2 is a plan view showing the paper holding release mechanism, Fig. 3 is a side sectional view showing the paper holding release mechanism, and Fig. 4 is a plan view showing the paper holding release mechanism. A plan view showing the paper bail return mechanism, Figure 5 is the X in Figure 4.
- An X-ray sectional view and FIGS. 6-7 show another example of the paper holding release mechanism, FIG. 6 is a partial perspective view, and FIG. 7 is a partial side sectional view. The platen 2, the printing paper 3, the paper bail 4, the carriage 10, the print head 11, and the operating lever 18 that constitutes the paper holding release mechanism. Locking protrusion 19° Locking spring 213 Rotating member 319 Operating member 33° Transmission gear mechanism 36, link 25 constituting the paper bail return mechanism. Engagement piece 28. Pressing body 29. Engagement protrusion 30°

Claims (1)

[Scope of Claims] 1. A platen (2), a carriage (10) movable along the longitudinal direction of the platen (2), and a carriage (10) mounted on the carriage (10) and configured to move the platen (
a print head (11) for printing on the printing paper (3) supported by the printer 2); and a paper that releasably presses and holds the printing paper (3) on the platen (2) above the printing position. Bale (
4); a paper press release mechanism that separates the paper bail (4) from a paper press position on the platen (2) and holds it at the separated position; ,
and a paper bail return mechanism that is activated by engagement with a part of the carriage (10) or the print head (11) to return the paper bail (4) from the separated position to the paper pressing position. A printer's paper holding device.