JPH072208Y2 - Printer media drive mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a medium traveling mechanism of a printer, and more particularly to a printer that can handle both medium conveyance by rotation of a platen and medium conveyance by a tractor. The present invention relates to a medium traveling mechanism.

[Conventional technology]

FIGS. 4 and 5 are side views showing a conventional example of a medium traveling mechanism of this type of printer. FIG. 4 shows a state in which a medium is conveyed by using a tractor, and FIG. The medium is being conveyed.

FIG. 6 is a perspective view of an essential part showing the state of FIG. 5 with the platen removed.

In the figure, 1 is a platen having a drive mechanism (not shown),
Reference numeral 2 is a medium inserted from a predetermined direction, 3 is a paper chute that guides the medium 2 to the platen 1, and the paper chute 3 is supported by fitting both ends of the paper chute 3 into a base frame (not shown) of the printer.

Reference numeral 4 denotes a paper support formed by punching a part of the paper chute 3 toward the platen 1, and reference numeral 5 denotes pinch rollers arranged in the axial direction so as to face the platen 1, and the paper support 4 serves to platen the medium 2. This is for smoothly feeding the medium 2 without causing wrinkles when the medium 2 is pinched and conveyed by the pinch roller 5.

That is, as shown in FIG. 6, the paper support 4 is formed between the plurality of pinch rollers 5 so as to correspond to the height when the pinch rollers 5 project from the paper chute 3 and come into pressure contact with the platen 1. This allows medium 2
Is guided in front of the pinch roller 5 so that no step is formed, and wrinkles are prevented from occurring.

A pressure spring 6 is welded to the paper chute 3, and the pinch roller 5 is axially supported at the tip of the pressure spring 6.

Reference numeral 7 denotes a release cam shaft which rotates in contact with the pressure spring 6, and the rotation of the release cam shaft 7 causes the pinch roller 5 to press and separate from the platen 1.

The operation of this configuration is as follows.

First, when the medium 2 is conveyed in the arrow direction by a tractor (not shown), the pressure spring 6 is pressed by the rotation of the release cam shaft 7 as shown in FIG.
This separates the pinch roller 5 from the platen 1,
In this state, the medium 2 is conveyed by the tractor.

Further, when the medium 2 is conveyed in the direction of the arrow by the rotation of the platen 1, the pressing force on the pressure spring 6 is released by the rotation of the release cam shaft 7 as shown in FIG. The pinch roller 5 is pressed against the platen 1 by the restoring force of the platen 1 and the medium is sandwiched between the platen 1 and the pinch roller 5. In this state, the platen 1 is rotated clockwise by a drive mechanism (not shown) to convey the medium 2. I do.

At this time, the pinch roller 5 rotates counterclockwise due to friction with the medium 2, whereby the medium 2 is smoothly transported.

[Problems to be solved by the invention]

However, in the above-described medium traveling mechanism of the printer, the paper support 4 protruding from the paper chute 3 to the platen 1 side is always in contact with the medium 2, so that as shown in FIG. When the medium 2 is moved away from the tractor by a tractor, it becomes a load. Therefore, the amount of slack in the left and right pin holes of the medium 2 fitted with the pin of the tractor becomes large, and the poor running of the medium 2 occurs. Further, there is a problem that a medium jam occurs.

The present invention has been made in order to solve such a problem, and when a medium is conveyed by a tractor, it is possible to eliminate a load on the medium and prevent a defective traveling or a medium jam, and a platen is used. An object of the present invention is to realize a medium traveling mechanism of a printer that can smoothly convey a medium without causing wrinkles when the medium is conveyed.

[Means for solving problems]

In order to achieve this object, the present invention can press and separate a platen having a drive mechanism, a paper chute that guides a medium inserted from a predetermined direction to the platen, and the paper chute side to and from the platen. And a release cam shaft for pressure contact and separation of the pinch roller, and by bringing the pinch roller into contact with or away from the platen, it is possible to convey the medium by rotation of the platen. In the medium traveling mechanism of the printer that supports both the conveyance of the medium by the tractor and the rotation of the release cam shaft, the release cam shaft presses the pinch roller against the platen. The release cam shaft moves to a position in contact with the medium, and the release cam shaft moves the pinch roller to the platen. The support collar, which moves to a position where it does not contact the medium when separated from the medium, is provided in the vicinity of the pinch roller so that the position contacting the medium is on the medium insertion side of the pinch roller. To do.

[Action]

In the present invention having such a structure, when the medium is conveyed by the tractor, when the pinch roller is separated from the platen by the rotation of the release cam shaft, the support collar rotates in association with the rotation of the release cam shaft, Since it moves to a position where it does not contact the medium, the medium can be conveyed without applying a load, and it is possible to prevent defective traveling and medium jamming.

Further, when the medium is conveyed by the rotation of the platen, when the pinch roller is brought into pressure contact with the platen by the rotation of the release cam shaft, the support collar rotates in conjunction with the rotation of the release cam shaft, and near the pinch roller. Since the medium is guided so as not to move to a position in contact with the medium and generate a step, it is possible to smoothly convey the medium without causing wrinkles.

〔Example〕

 Embodiments will be described below with reference to the drawings.

1 and 2 are side views showing an embodiment of a medium traveling mechanism of a printer according to the present invention. FIG. 1 is a state in which a medium is conveyed using a tractor, and FIG. 2 is a rotation of a platen. The medium is being conveyed by.

FIG. 3 is a perspective view of an essential part showing the state of FIG. 2 with the platen removed.

In the figure, 1 is a platen, and 2 is a medium to be inserted from a predetermined direction.

A paper chute 8 guides the medium 2 to the platen 1. The paper chute 8 is supported by fitting both ends of the paper chute 8 into a base frame (not shown) of the printer.

Reference numeral 9 is a pinch roller arranged facing the platen 1 in the axial direction, and 10 is a pressure spring welded to the back surface of the paper chute 8. The pinch roller 9 is axially supported at the tip of the pressure spring 10. ing.

Reference numeral 11 denotes a release cam shaft that rotates in contact with the pressure spring 10. The rotation of the release cam shaft 11 causes the pinch roller 9 to press and separate from the platen 1.

Reference numeral 12 denotes a support collar, which has two flat surfaces 12a and 12b having a fan shape in cross section and forming a V shape.

The support collar 12 is fixed to the release cam shaft 11 so as to be positioned between the plurality of pinch rollers 9 and on the medium insertion side with respect to the position where each pinch roller 9 contacts the medium 2. The paper chute 8 is provided with a window 13 so as to correspond to the support collar 12.

Where the support collar 12 and the release camshaft
The interlocking relationship of 11 will be explained. When the release cam shaft 11 separates the pinch roller 9 from the platen 1, one flat surface 12a of the support collar 12 within the window portion 13 as shown in FIG. It has the same surface as the paper chute 8, and the release camshaft 11 has a pinch roller 9
When the platen is pressed against the platen 1, the other flat surface 12b of the support collar 12 is set to project obliquely from the window 13 and have the same height as the pinch roller 5, as shown in FIG. Has been done.

Next, the operation of the above configuration will be described.

First, when the medium 2 is conveyed in the arrow direction by a tractor (not shown), the pressure spring 6 is pressed by the rotation of the release cam shaft 7 as shown in FIG.
This separates the pinch roller 5 from the platen 1.

At this time, the support collar 12 has the release camshaft 7
The flat surface 12a of the support collar 12 forms the same surface as the paper chute 8 in the window 13 in association with the rotation.

Therefore, when the medium 2 is conveyed by the tractor in this state, the medium 2 is smoothly conveyed without being loaded.

On the other hand, when the medium 2 is conveyed in the arrow direction by the rotation of the platen 1, the pressing force to the pressure spring 6 is released by the rotation of the release cam shaft 7 as shown in FIG. 2, and the pressure spring 6 at this time is released. The pinch roller 5 is brought into pressure contact with the platen 1 by the restoring force, and the medium 2 is sandwiched between the platen 1 and the pinch roller 5.

At this time, the support collar 12 has the release camshaft 7
And the other flat surface 12b of the support collar 12 projects obliquely from the window 13 to a height equivalent to that of the pinch roller 5, and the medium 2 is platen so as not to cause a step. Guide between 1 and pinch roller 5.

Therefore, in this state, when the platen 1 is rotated clockwise by a drive mechanism (not shown) to carry the medium 2,
At this time, the pinch roller 5 rotates counterclockwise due to the friction with the medium 2, whereby the medium 2 is smoothly transported.

[Effect of device]

As described above, according to the present invention, the release cam shaft rotates in association with the rotation of the release cam shaft, and the release cam shaft moves to a position in contact with the medium when the pinch roller is pressed against the platen. A support collar that moves to a position not in contact with the medium when the pinch roller is separated from the platen is provided so that the position near the pinch roller and the position in contact with the medium is on the medium insertion side of the pinch roller. Since it is configured to be provided, when the medium is transported by the tractor, it is possible to transport the medium without applying a load to the medium, and it is possible to obtain the effect that it is possible to prevent defective traveling and medium jamming. When the medium is conveyed by the rotation of the platen, the medium is guided so as not to generate a step, so the medium wrinkles. Effect that it is possible to smoothly conveyed without a can be obtained.

[Brief description of drawings]

1 and 2 are side views showing an embodiment of a medium traveling mechanism of a printer according to the present invention, and FIG. 3 is a perspective view of a main part showing the state of FIG. 2 without a platen, FIG. Fifth
FIG. 6 is a side view showing a conventional example of a medium traveling mechanism of this type of printer, and FIG. 6 is a perspective view of a principal part showing the state of FIG. 1 ... Platen, 2 ... Medium, 8 ... Paper chute, 9 ...
Pinch roller, 10 ... Pressure spring, 11 ... Release cam shaft, 12 ... Support collar, 12a, 12b ... Flat surface

Claims (1)

[Scope of utility model registration request] 1. A platen having a drive mechanism, a paper chute that guides a medium to be inserted from a predetermined direction to the platen, and pressure contact with the platen from the paper chute side,
A pinch roller disposed so as to be separated from each other, and a release cam shaft for press contact and separation of the pinch roller, and by pressing or separating the pinch roller to or from the platen, a medium generated by rotation of the platen In the medium traveling mechanism of the printer that supports both the conveyance of the medium and the conveyance of the medium by the tractor, the medium rotates in association with the rotation of the release cam shaft, and the release cam shaft presses the pinch roller against the platen. A support collar that moves to a position in contact with the medium when the release cam shaft moves the pinch roller away from the platen and moves to a position that does not contact the medium in the vicinity of the pinch roller, and It is arranged so that the position in contact with the medium is on the medium insertion side of the pinch roller. Medium conveying mechanism of the printer to symptoms.