JP2732416B2 - Passbook printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus, and more particularly to a passbook printing apparatus suitable for printing a plurality of media having different thicknesses, so-called passbooks.

[0002]

2. Description of the Related Art In a conventional printing apparatus, a printing medium is rotated by a guide provided on a printing carrier, thereby pressing a printing medium with a platen and confirming that the stepping motor has stopped. The printing was performed while maintaining a fixed distance between the printing medium and the printing head. Related devices of this type include, for example, JP-A-58-203072 and JP-A-2-113979.

[0003]

In the above prior art, the step motor is rotated, the medium is pressed against the guide by the platen, and after the step motor stops, the step motor must be rotated reversely, which makes the control complicated. Yes, it takes time, and the print medium separates from the guides, so that it does not stick, causing a loss of the impact force of the print head, and at the same time, generating noise when detecting the stop of the rotation of the step motor. Atsuta. SUMMARY OF THE INVENTION It is an object of the present invention to efficiently print on print media having different thicknesses in view of the problems of the related art.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a reference guide which always keeps a constant interval when the print head moves left and right, a platen for pressing the print medium on the reference guide, and a motor via an elastic member. This is achieved by engaging the eccentric shaft connected to the platen with the platen and pressing the platen by the eccentric shaft by rotating the motor, thereby moving the platen.

[0005]

In the printing apparatus according to the present invention, the printing medium conveyed on the platen is rotated by a predetermined amount of the motor.
It is pressed by the reference guide by the platen, and is kept at a constant interval and flat with respect to the print head. At this time, since the eccentric shaft for moving the platen obtains the rotating force from the motor via the elastic member, a thick medium can be pressed with a strong pressing force, and a thin medium can be pressed with a low pressing force. As a result, the printing head can be efficiently printed with little loss of the impact force of the printing head.
Also, since the operation of the motor is completed with a fixed amount of rotation regardless of the thickness of the print medium, there is no need for reverse rotation after detecting the thickness,
The control is simplified, the operation is completed in a short time, and there is no noise when detecting the step-out of the step motor. Further, in the present invention, since the platen is pressed by the eccentric shaft, the pressing force is constant over the entire length of the platen, and the printing medium can be pressed efficiently against the reference guide.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 2 is a diagram showing an entire embodiment of the present invention. In FIG. 2, a printing medium 1 is inserted from an inserter 2 and is transported by a roller A3 and a roller B4.
Is conveyed to a platen 9, where a desired print is performed by a print head 7, and then controlled by a controller 6 so as to be discharged to an inserter 2. Examples of the print medium 1 include media of various thicknesses, such as a slip having a uniform thickness, a multi-leaf slip, or a passbook having a stitch. The printing medium 1 is pressed by the reference guide 8 during printing while the platen shaft 1
Predetermined information is printed by a print head 7 which is held by a platen 9 fixed to be rotated by a platen arm 10 around a center 1 and moves in a row direction at a constant interval from the reference guide 8. In order to maintain the fixed interval, the print head may be held by a print carrier having a mechanism for that purpose, and a part of the print head holds the fixed interval by following a reference guide. May be printed.

FIG. 1 is a cross-sectional view taken along the line AA of FIG. 2 and shows the main configuration of a passbook printing apparatus characteristic of the present invention and explains the operation of a platen. The eccentric shaft 12 includes a pair of left and right bearings 12b, an eccentric shaft 12a, and a shaft 12c. The eccentric shaft 12 is rotatably held by the side frames R20 and 21 by a pair of left and right bushes 19a and 19b. I have. FIG. 3 shows the eccentric shaft 12 viewed from the right side of FIG. One of the bushes 19b is fixed to the side frame R20 in a finely adjustable manner so that the parallelism of the surface of the platen 9 pressed by the reference guide 8 and the eccentric shaft 12 in contact with the print medium 1 is within an allowable value. Have been. However, when the accumulation of the component accuracy and the assembly accuracy falls within the allowable values, the adjustment mechanism may be deleted. Further, in the embodiment shown in FIG. 1, the pair of left and right bearing portions 12b presses the platen 9, but a configuration in which the platen 9 is pressed by the entire eccentric shaft may be adopted. Needless to say.

[0008] A shear plate 13 is fixed to the shaft portion 12c, and the shaft portion 12c holds the pulley 16 in a state in which it can idle. A spring 15 is disposed between the shear plate 13 and the pulley 16, and each end of the spring 15 is connected to the shear plate 13 and the pulley 1 respectively.
6, whereby torque is transmitted between the pulley 16 and the shear plate 13. The stopper 13a provided on the shear plate 13 is a pulley in a direction opposing the rotational force generated by the spring 15 so that the rotational force of the spring 15 is charged by a fixed force and the relative position of the two parts is not rotated more than a predetermined amount. 16 are engaged with the engaging portions 16a. FIG. 4 is a view of the portion of the pulley 16 of FIG. 1 viewed from the left side to show this engaged state.

The pulley 16 is connected to a motor 18 (a step motor in this embodiment) by a timing belt 17, and the driving force of the motor 18 is transmitted to the eccentric shaft 12 via a spring 15 and a shear plate 13. Is done. Further, the shear plate 13 is provided with a shear plate groove 13b for determining an initial position of the eccentric shaft 12 by a sensor 14 when the apparatus is started, and detects the initial position when the apparatus is started. Information on this initial position is set in the controller 6. After the start-up of the apparatus, the motor 18 is controlled based on this position. Printing medium 1
During the transfer, the motor 18 is controlled so that the platen 9 is lowered to the lowermost position so as not to cause a transfer resistance. Next, during printing, the motor 18 is rotated in the X arrow direction from this state by a predetermined amount, and the motor 18 is controlled to a holding state (a state in which the motor 18 rotates and keeps a constant rotation angle). At this time, the driving force is transmitted to the eccentric shaft 12 via the pulley 16, the spring 15, and the shear plate 13 as described above, and presses the platen 9 in the Y arrow direction.

When the platen 9 presses the printing medium 1 against the reference guide 8, the stopper 13 engaged with the pulley 16
Since a is separated from the engaging portion 16a of the pulley 16, the eccentric shaft 12 rotates by the charging force of the spring 15, and presses the platen 9. Therefore, the printing medium 1
When the thickness is small, the force applied to the spring 15 is small, and the reference guide 8 is not overloaded. On the other hand, when the print medium 1 is thick as shown in FIG.
5, a large power is charged, a pressing force necessary for squeezing the print medium 1 is obtained, and the loss of the impact force of the print head 7 can be reduced and printing can be performed efficiently.

Further, since the driving force is always obtained by rotating the motor 18 by a fixed amount regardless of the thickness of the print medium 1, the detection of the medium thickness is not required, and simple and short-time control is possible. Further, since the platen 9 is directly pressed by the eccentric shaft 12, the pressing force can be constant over the entire length of the platen 9. Although one embodiment has been described above, the specific structure of each part in the present invention is not limited to the embodiment shown in the drawings, and may be any structure having an initial function. For example,
Although the eccentric shaft 12 is held by the motor 18 during printing, a separate brake mechanism may be provided. Further, the eccentric shaft is not limited to the example shown in the embodiment, but may be any configuration that generates a force for pressing the platen 8 by rotation.

[0012]

As described above, according to the present invention,
Efficient and stable printing of multiple thicknesses on printing media such as cut sheets and passbooks without the need for complicated control.
There is an effect that it can be performed in a short time.

[Brief description of the drawings]

FIG. 1 shows a main configuration of a passbook printing apparatus, and FIG.
It is AA sectional drawing of a figure.

FIG. 2 is an overall view of a passbook printing apparatus.

FIG. 3 is a view of the eccentric shaft 12 of FIG. 1 as viewed from the right side of FIG.

FIG. 4 is a view of a pulley 16 of FIG. 1 as viewed from the left side of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printing medium 5 Conveyance path 6 Controller 7 Printing head 8 Reference guide 9 Platen 12 Eccentric shaft 12a Eccentric shaft part 12b Bearing part 12c Shaft part 13 Shear plate 13a Stopper 13b Shear plate groove 15 Spring 16 Pulley 16a Engagement Timing belt 18 Motor 19a, 19b Bush

Claims (3)

(57) [Claims] 1. A passbook printing apparatus for printing information on a print medium by pressing a print medium such as a passbook and a form with a platen against a reference guide facing the platen, wherein the surface opposite to the surface of the platen with respect to the reference guide is provided. An eccentric shaft placed at an engaging position, a shear plate fixed to the eccentric shaft, a pulley held to the eccentric shaft so as to be able to idle, a stopper provided on the shear plate, An engaging portion provided on the pulley and engageable with the stopper, and one end is fixed to the pulley and the other end is fixed to the shear plate and disposed between the pulley and the shear plate so as to surround the eccentric shaft. And a motor for driving the pulley. The pulley is driven by the motor, and the eccentric shaft rotates to cause the platen to move the printing medium to the reference guide. When the motor is brought into the holding state by being pressed against the print medium, the force charged by the spring is reduced when the print medium is thin, and the force charged by the spring is increased when the print medium is thick. A passbook type printing apparatus comprising a printing mechanism for changing a pressing force between the reference guide and a platen according to a thickness. 2. The passbook printing apparatus according to claim 1, wherein the printing head has a printing carrier portion for holding the printing head so as to always keep a constant distance from the reference guide. 3. A passbook printing apparatus according to claim 1, wherein a part of the print head is printed following the reference guide so that the print head always keeps a fixed distance from the reference guide. Kind printing device.