JPH08259029A - Printing paper conveying device for printer - Google Patents

Abstract

PURPOSE: To prevent the occurrence of wrinkles or the like that causes poor printing on the printing paper at the time of conveyence by making up the printing paper conveying device of first rollers of a large diameter for abutting a pinch roller on a feeding roller, and second rollers of a diameter smaller than the larger diameter roller. CONSTITUTION: A first shaft 7a is provided below a feeding roller 6, and a first pinch roller 7' is provided in the central part of the first shaft 7a, and first rollers 10a of a large diameter integrally formed with a second roller 10b of a diameter smaller than that of the first roller 10a are provided on both ends of the first shaft 7a. On the other hand, a second, shaft 8a is provided above the feeding roller 6, and second pinch rollers 8, 8' are provided to the second shaft 8a at prescribed intervals. Thereby, the slackening caused at the time when a printing paper is fed can be escaped by the gaps, so that the deformation of the printing paper is not produced, and the wrinkles or the like that causes poor printing can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing paper conveying device for a printer.

[0002]

2. Description of the Related Art FIG. 2 is a schematic side view showing a structural example of a main part of a conventional printing paper conveying device for a printer. In the figure, reference numeral 1 is a paper cassette having a corner claw T attached to one end thereof, and contains printing papers 2, 2 ,. Reference numeral 3 is a pickup roller having a substantially semicircular cross section, and a shaft 3a attached to the central axis of the pickup roller is driven by a motor (not shown) to feed the uppermost printing paper 2 in the paper cassette 1. .

Paper guides 4 and 5 guide the printing paper 2 fed by the pickup roller 3. Reference numeral 6 denotes a feed roller having a shaft 6a attached to its central axis, and conveys the printing paper 2. The rotational force of the above-mentioned motor is transmitted to the shaft 6a of the feed roller 6 via a drive system including a belt, a pulley and a gear (not shown). Reference numeral 7 denotes a first pinch roller, which is attached to the first shaft 7a at a predetermined interval below the feed roller 6 such that the outer peripheral surface of the first pinch roller abuts the outer peripheral surface of the feed roller 6. (See Figure 3). The first shaft 7a has a pressing force P at two points between the first pinch rollers 7 and 7 by a torsion spring (not shown).
Is urged in the direction of the feed roller 6.

In FIG. 2, reference numeral 8 denotes a second pinch roller, which is located above the feed roller 6 so that its outer peripheral surface abuts on the outer peripheral surface of the feed roller 6.
Attached to. As shown in FIG. 3, a second pinch roller 8 ′ having a width larger than that of the second pinch roller 8 is provided at the center of the second shaft 8a, and a second pinch roller 8 ′ is provided at both ends of the second pinch roller 8 ′. Two pinch rollers 8 and 8 are provided respectively. Further, the second shaft 8a is biased toward the feed roller 6 by the pressing force P at two points between the second pinch rollers 8 and 8'by a torsion spring (not shown).

In FIG. 2, 9 is a paper guide,
It is provided on the left side of the paper guide 4 and the feed roller 6 and guides the conveyed print paper 2 between the feed roller 6 and the second pinch roller 8.

In the above structure, when the motor is driven, the pickup roller 3 is rotationally driven in the direction shown by the arrow in FIG. 2, and the feed roller 6 is rotationally driven in conjunction with this rotation. Further, when the feed roller 6 is rotationally driven, the first pinch rollers 7, 7,
... and the second pinch rollers 8, 8 ', 8 respectively rotate in the direction of the arrow shown in FIG. And the pickup roller 3
When the outer peripheral surface of the sheet abuts on the uppermost printing sheet 2 in the sheet cassette 1, the printing sheet 2 is fed out, and the printing sheet 2 goes over the corner claw T of the sheet cassette 1 toward the feed roller 6. The paper is fed while being guided by the paper guides 4 and 5, and its leading end is sandwiched between the feed roller 6 and the first pinch rollers 7, 7, .... Further, the printing paper 2 is conveyed while being guided by the paper guide 9 while being in pressure contact with the feed roller 6 and the first pinch rollers 7, 7, .... Then, the printing paper 2 is fed to the feeding roller 6 and the second
In a state where it is sandwiched between the pinch rollers 8, 8 ', 8 of FIG.

By the way, in the printing paper conveying device of the printer shown in FIG. 2, the leading end of the printing paper 2 is the feed roller 6.
When sandwiched between the first pinch roller 7, and the first pinch roller 7, there is a problem that the leading edge of the printing paper 2 is wavy as shown in FIG. This is because the interval between the first pinch rollers 7, 7, ... Is wide, and the leading edge of the printing paper 2 swells in this interval. When the printing paper 2 is conveyed in a wavy state and is sandwiched between the feed roller 6 and the second pinch rollers 8, 8 ', 8, wrinkles are generated in the printing paper 2, which causes defective printing. To do.

Therefore, in order to solve the above problem, FIG.
In place of the two first pinch rollers 7, 7 provided in the vicinity of the center of the first shaft 7a shown in FIG. 5, a first pinch roller having a width wider than that of the pinch roller 7 as shown in FIG. It is possible to attach 7 '. By attaching this first pinch roller 7 ', the feed roller 6
Of the first pinch rollers 7, 7 ′, 7 are in contact with substantially the entire outer peripheral surface thereof. As a result, when the printing paper 2 is conveyed, the printing paper 2 is in close contact with almost the entire outer peripheral surface of the feeding roller 6 and the feeding roller 6 and the first pinch rollers 7, 7 ′, 7
Since it is sandwiched between and, the waviness does not occur at the leading edge of the printing paper 2.

[0009]

By the way, in the above-mentioned conventional printer printing paper conveying apparatus, the corrugation of the printing paper 2 occurs when the feed roller 6 and the first pinch rollers 7, 7 ', 7 are sandwiched. Although there is an advantage that the printing paper 2 is lost, the slack of the printing paper 2 which occurs when the printing paper 2 is fed over the corner claw T of the paper cassette 1 is first pinched by the pressing force P. There is a drawback that the printing paper 2 is gathered in the gap between the rollers 7 and 7'and is deformed such as streak-like wrinkles, corner folds, and tip turning. The present invention has been made under such a background, and an object of the present invention is to provide a printing paper carrying device for a printer, which can prevent the occurrence of wrinkles or the like that cause printing defects on the printing paper during carrying. To do.

[0010]

According to a first aspect of the present invention, there is provided a print sheet conveying device for a printer which conveys a print sheet while sandwiching the print sheet between a feed roller and a pinch roller, wherein the pinch roller is the feed roller. Large diameter first contact
And a second roller having a diameter smaller than that of the large roller.

According to a second aspect of the invention, there is provided a feed roller,
A first shaft provided parallel to the rotation axis of the feed roller, and a plurality of first shafts arranged at a predetermined distance from the first shaft, the outer peripheral surfaces of which are in contact with the outer peripheral surface of the feed roller. A first pinch roller, a second shaft provided in parallel to the rotation axis of the feed roller, and a second shaft, which are arranged at a predetermined distance from each other, and each outer peripheral surface of the feed roller is A printing paper conveying device for a printer, comprising: a plurality of second pinch rollers that are in contact with the outer peripheral surface; and a guide member that guides the printing paper between the first pinch roller and the second pinch roller. Among the plurality of first pinch rollers, the first pinch rollers on both sides are integrally formed with a first roller having a large diameter and a second roller having a smaller diameter than the first roller. It is characterized by being.

[0012]

According to the present invention, when the feed roller is rotationally driven, the pinch roller rotates in conjunction with this. And
When the leading edge of the fed printing paper is sandwiched between the feed roller and the pinch roller, the printing paper comes into close contact with almost the entire outer peripheral surface of the feed roller, so that waviness does not occur.
Further, the slack of the printing paper, which occurs when the paper is fed, is escaped by the gap formed between the second roller of the pinch roller and the feed roller. As a result, the printing paper is
It is conveyed while being pinched between the feed roller and the pinch roller while its tip is kept substantially straight.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an example of the configuration of a carrying section of a printing paper carrying apparatus for a printer according to an embodiment of the present invention. In this figure, parts corresponding to those shown in FIG. The description is omitted. In the transport section of the printing paper transport apparatus shown in this figure, instead of the first pinch rollers 7, 7 shown in FIG. 5, first pinch rollers 10,
10 is newly provided. The first pinch rollers 10 and 10 integrally include a first roller 10a having the same diameter as the first pinch roller 7 shown in FIG. 5 and a second roller 10b having a smaller diameter than the first roller 10a. Has been formed.

In the above structure, first, when the motor is driven, the printing paper 2 shown in FIG. 2 is fed by the pickup roller 3 toward the feed roller 6. At the time of this paper feeding, the slack is generated on the printing paper 2. And
The leading edge of the printing paper 2 is sandwiched between the feed roller 6 and the first pinch rollers 10, 7 ', 10 shown in FIG. At this time, the leading edge of the printing paper 2 has a high degree of close contact with the feed roller 6 and is therefore sandwiched without waviness. further,
The slack of the printing paper 2 generated at the time of feeding the paper is released by the gap formed between the second roller 10b of the first pinch roller 10 and the feed roller 6. As a result, the printing paper 2 is not
After passing through the pinch rollers 8, 8 ′, 8 of FIG.

[0015]

As described above, according to the present invention,
The printing paper is sandwiched between the feeding roller and the pinch roller without waviness in a state where the printing paper is in close contact with the feeding roller over substantially the entire outer peripheral surface thereof. At the same time, the slack generated when the printing paper is fed is released by the gap, so that the printing paper is not deformed. Therefore, the printing paper is conveyed while the front end thereof is kept substantially straight, whereby wrinkles and the like can be prevented.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration example of a conveyance unit of a printing paper conveyance device of a printer according to an embodiment of the present invention.

FIG. 2 is a schematic side view showing a configuration example of a main part of a printing paper conveyance device of a conventional printer.

FIG. 3 is a perspective view showing a configuration of a carrying section of the printing paper carrying device shown in FIG.

FIG. 4 is a side view showing how the leading edge of the printing paper 2 is wavy.

FIG. 5 is a view showing a conventional printing paper conveying device of a printer,
It is a perspective view which shows the other structural example of a conveyance part.

[Explanation of reference numerals] 2 printing paper 6 feed roller 7 ', 10 first pinch roller 7a first shaft 8,8' second pinch roller 8a second shaft 10a first roller 10b second roller

Claims (2)

[Claims] 1. A printing paper transporting device for a printer, which transports a printing paper while sandwiching the printing paper between a feeding roller and a pinch roller, comprising: a large-diameter first roller that abuts the pinch roller on the feeding roller; And a second roller having a smaller diameter than the above roller. 2. A feed roller, a first shaft provided in parallel with a rotation axis of the feed roller, a first shaft provided at a predetermined interval, and an outer peripheral surface of the feed roller. A plurality of first pinch rollers that are in contact with the outer peripheral surface of the second shaft, a second shaft that is provided in parallel with the rotation axis of the feed roller, and a second shaft that is arranged at predetermined intervals. A plurality of second pinch rollers, each outer peripheral surface of which is in contact with the outer peripheral surface of the feed roller, and a guide member which guides the printing paper between the first pinch roller and the second pinch roller. In the printing paper conveyance device of a printer having a plurality of first pinch rollers, the first pinch rollers on both sides of the plurality of first pinch rollers have a large diameter first roller and a second diameter smaller than the first roller. The roller of Printing paper conveying apparatus of a printer according to claim.