JPS62790B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printer, and particularly to a printer that facilitates setting of printing paper when printing on another printing paper on top of the printing paper that has already been set.

For example, in banking, when information is printed on a certificate (ticket), the exact same information is printed on a copy of the paper, which serves as a copy for the bank.
For this purpose, the same information is printed on the authentication paper and the copy paper by placing them side by side in the longitudinal direction of the platen. However, the copy paper is made into a continuous paper, and the authentication paper is stacked on top of it and set at the printing position, so that the same information can be printed at once. It is common to authenticate and print on copy paper at the same time. The latter is advantageous over the former because printing only needs to be done once.

However, in the latter case, the authentication must be inserted where the continuous paper as a copy paper has already been set. Generally, the gap between the platen member and the print section including the print head is small in order to increase the speed. Therefore, there is a drawback that the authentication is not set in the printing position smoothly.

In order to solve this problem, two techniques have been proposed in the past. One is to increase the gap between the printing part and the platen member by retracting the entire platen mechanism, and the other is to increase the gap by retracting only the platen member. .

The former moves the entire platen mechanism consisting of the platen member, the paper transport section (sprocket or tractor), their supporting frame, etc., and the moving parts are heavy and require a large driving source. The latter does not require a large driving source because only the platen member is moved, but even if only the platen member is retracted, the continuous paper remains in the printing position, and in cases such as weak authentication, the continuous paper prevents insertion. The problem is that

Further, when the platen member is retracted, the platen becomes free to rotate, and the platen rotates due to vibration or the like. As a result, when the platen is returned to its original position, the gear provided on the platen and the gear connected to the line feed motor do not mesh smoothly, and the printing paper may be misaligned.

The present invention minimizes the mechanism for retracting when printing paper is set on the platen by an inserter, and
To provide a printer whose platen does not rotate during evacuation.

A printer according to the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a platen mechanism of a printer according to the present invention, and FIG. 2 is a side view of FIG. 1. 1st
1 is a frame, and this frame 1 includes a platen member (platen roll) 2.
is rotatably supported. Platen roll 2
has a circular cross section, and a gear 3 is fixed to one end thereof. A gear 5 is fixed to this gear 3 via an idle gear 4, and this gear 5 is engaged with a shaft 6. A pulley 7 is fixed to the shaft 6, and a timing belt 8 is attached to this pulley 7.
is stretched, and the platen roll 2 is rotated by moving the timing belt 8 using a line feed drive source such as a pulse motor.

A pair of retraction levers 9 are provided at both ends of the platen roll 2.
It is rotatably supported at one end of the levers 9a and 9b, and an engagement hole is provided at the other end of the lever 9a and 9b. Cams 10a and 10b are fitted into these engagement holes. These cams 10a, 10b are connected to the center of the shaft 11 and the cams 10a, 10b.
is fixed with its center eccentric.

12 is a continuous paper (first printing paper), which is set so as to wrap around a part of the outer periphery of the platen roll 2. This continuous paper 12 has feed holes provided at equal pitches on both sides, and the tractor 13
When the pins a and 13b engage with the feed holes, the continuous paper 12 is moved in the direction of the arrow.

14 is a guide plate, and the continuous paper 12 is transported on this guide plate 14 to reach the platen roll 2.

Blocks 15a, 15 are provided at both ends of the guide plate 14.
b is fixed, and these blocks 15a, 15
b has an engagement hole. This engagement light has cam 1.
6a and 16b are fitted. Cam 16a, 16
b is fixed with respect to the retraction shaft 11 with the center of the shaft 11 and the centers of the cams 16a, 16b being eccentric.

The retraction shaft 11 further includes cams 17a and 17b.
is installed eccentrically. Both cams 17a, 17
cam follower levers 18a and 18b are provided in such a manner that they are always in contact with each other. This is achieved by spring 18. Camfluoroareva 18a, 1
A shaft 19 is fixed to the other end of 8b, and a plurality of rollers 20 are fixed to this shaft 19.

Reference numeral 21 denotes an inserter, which is used to set a cut sheet (second printing paper) into the gap between the continuous printing paper 12 and the printing section 23 including the print head 22, and manually or automatically insert the cut sheet into the printer. , is ejected. In FIG. 1, only a portion of the inserter 21 is shown broken away.

A drive source such as a pulse motor is connected to one end of the evacuation shaft 11 either directly or via a transmission means such as a gear or a belt. When a drive source such as a DC motor or an AC motor, which requires complicated positioning control, is used, a half-turn clutch may be provided between the motor and the shaft 11.

A detent gear 24 is fixed to the platen roll 2, and a detent pole 25 can be engaged with the detent gear 24. The detent pole 25 is connected to the detent gear 2 by a spring 26.
However, when the gear 3 of the platen roll 2 and the idle gear 4 are engaged, that is, when the platen roll 2 is in a state where the changeover operation is possible, the detent pole 25 is biased to engage the detent gear 24. The detent pole 25 is restricted by a stopper (not shown) so as not to engage with the detent pole 25.

The print head 22 is supported by a carrier,
This carrier reciprocates in the longitudinal direction of the platen roll 2 by a space drive source such as a space motor. The print head 22 prints characters in synchronization with the movement.

A platen knob 27 is provided at one end of the shaft 6, and by rotating the platen knob 27, the continuous paper 12 can be manually fed. A pathway 28 is provided below the platen roll 2 and the printing section 23, and guides the cut when it is inserted.

Next, the operation will be explained. First, the single sheet is inserter 2.
1 and when a suction command arrives, the cut sheet is suctioned downward by a roller mechanism built into the inserter 21. This suction command causes the pulse motor (retreat drive source) to start rotating. As a result, the cams 10a, 10b, 16a, 16b, 17
a, 17b are rotated, but the cams 17a, 17b
is slightly ahead of the cams 10a, 10b, 16a, 16b in phase, and first the roller 20 is moved downward by the cams 17a, 17b, and the continuous paper 12
is pressed against the guide plate 14. When the shaft 11 further rotates, the retraction levers 9a and 9b are moved to the right by the cams 10a and 10b, and as a result, the platen roll 2 is retracted so that the gap with the print head 22 is increased. At the same time, continuous paper 12
The evacuation operation also progresses. That is cam 16a, 16
As b rotates, the guide plate 14 moves to the right, moving the continuous paper 12 pressed by the rollers 20. This increases the gap between print head 22 and continuous paper 12.

In this way, the platen roll 2, the continuous paper 12
As a result of the retracting operation, the obstruction to the inhaled ticket has been removed, and the ticket is guided to the pathway 28 via the inserter 21. When the specified print line of the cut sheet is set at the print position,
Since the pulse motor rotates further, the cams 10a,
10b connects the platen roll 2 to the print head 2.
Move in two directions. At the same time, the cam 16a,
Since the guide plate 14 is also returned to its original position by means of the roller 16b, the continuous paper 12 is also returned to its original state, and the roller 20 is separated from the guide plate 14 at the end of its operation. The return of the continuous paper 12 does not have to be carried out by the return of the guide plate 14; the roller 20 may be released from the guide plate 14 at the beginning of return, and the continuous paper 12 may be returned by the platen roll 2. In that case, the return of the guide plate 14 does not need to be synchronized with the return of the platen roll 2.

When the platen roll 2 begins to retreat, the gear 3 and the idle gear 4 disengage, and the platen roll 2 becomes free to rotate.However, the detent pole 25 engages the detent gear 24, so the rotation of the platen roll 2 is stopped. be hindered. Therefore, when the platen roll 2 returns from the retracted position, the gear 3 and the idle gear 4 mesh smoothly.

FIG. 3 shows another example according to the present invention, in which the evacuation operation of the continuous paper 12 is performed by a mechanism different from that in FIG. 2. In FIG. 3, parts that are the same as in FIGS. 1 and 2 are given the same reference numerals. A cam-equipped rack 30 is fixed to the retracting levers 9a, 9b, and a pin-on 31 is fixed to the shaft 19 in addition to the roller 20. The shaft 19 is rotatably supported by levers 18a, 18b as in FIG. 2, but the cams 17a, 17b
There is no equivalent, and the pin-on 31 is constantly pressed against the rack 30 by the spring 18. Rack 30 has teeth and a cam that engage pin-on 31. The cam surface is higher than the tooth surface, and when the pinion 31 is engaged with the teeth of the rack, the roller 20 is pressed against the guide plate 14 via the continuous paper, and when it rides on the cam surface, the roller 20 is pressed against the guide plate 14. Move away from 14.

To explain the operation in FIG. 3, when the evacuation shaft 11 is rotated clockwise in FIG. 3 by the pulse motor (evacuation drive source), the levers 9a and 9b move rightward. As a result, the rack 30 also moves to the right, so that the pin-on 31 is lowered from the cam surface to the tooth surface, so that the roller 20 presses the continuous paper 12 against the guide plate 14. When the levers 9a and 9b move further to the right, the pinion 31 engages with the teeth of the rack and rotates. As a result, the roller 20 also rotates, and the continuous paper 12 is transported rightward as the roller 20 rotates. Platen roll 2 and continuous paper 1
2 completely reaches the retracted position, the gap between the print head and the continuous paper 12 increases, and the inserter 21 can smoothly suck in the slip. The return operation is performed by further rotating the shaft 11 to release the lever 9.
This is done by moving the pinions a and 9b to the left, and at the end of the movement, the pinion 31 rides on the cam surface of the rack, freeing the continuous paper 12.

Note that the platen knob 27 may be fixed to the shaft of the platen roll 2;
It is preferable to engage the shaft 6 because it moves in synchronization with the evacuation operation of the printing paper, which is often undesirable. It goes without saying that the printing head of the printing section may be of various types such as a wire dot type, a type matrix type, or a thermal type.

As explained above, in the case of sheet setting using an inserter, a paper evacuation mechanism is provided and this mechanism is operated in conjunction with the platen evacuation mechanism, so that printing sheets can be set smoothly by also retracting the printing paper. becomes possible. Even the weakest single sheets can be set reliably.

In addition, since the detent mechanism prevents the platen member from rotating during retraction, when the platen member returns, the gear fixed to the platen and the gear connected to the line feed drive source can mesh smoothly, and the printing paper There will be no misalignment.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a printer according to the present invention;
The figure is a side view of FIG. 1, showing only the platen mechanism. FIG. 3 is a schematic side view of a platen mechanism showing another example of the present invention. In the figure, 2... platen roll, 9a, 9b...
Retraction lever, 10a, 10b, 16a, 16b, 1
7a, 17b...cam, 11...shaft, 12
...Continuous paper, 13a, 13b...Tractor, 1
4...Guide plate, 20...Roller, 22...Printing head, 23...Printing section.

Claims (1)

[Scope of Claims] 1. A platen member, a printing section including a printing head facing the platen member with a gap therebetween, and a sheet for transporting a first printing paper set in the gap between the printing section and the platen member. a transfer section, an inserter that sets a second print sheet between the print section and the first print sheet, a platen retraction mechanism that retracts the platen member so that the gap between the platen member and the print section is increased; a paper retracting mechanism that retracts the first print paper so that the gap between the first print paper and the printing section is increased; a gear that rotates the platen member; and a gear fixed to the platen member; a detent mechanism including a detent gear fixed to the platen member and a detent pole that engages with the detent gear in conjunction with the retracting operation of the platen to prevent rotation of the platen. When the second printing paper is set by the inserter, the platen retraction mechanism causes the platen member to be retracted, and in conjunction with the retraction operation of the platen member, the first printing paper is retracted, and the detent pole is moved to the detent gear. A printer characterized in that: 2. The printer according to claim 1, wherein the platen retraction mechanism and the paper retraction mechanism are driven by the same drive source.