JPH0252835A - Sheet feeding device - Google Patents

Abstract

PURPOSE:To enable the stable feed, freed from unevenness in feed, of sheets and to reduce the generation of a constant curl by a method wherein a roll paper containing part is movable to a feed roller by means of a resilient member, and a paper is guided by means of the outer periphery of an idler roller located between a roll paper in the containing part and the roller to feed it to the roller. CONSTITUTION:During the feed of a sheet, a feed roller 15 is driven with the aid of a feed motor 16, and a roller 15 is rotated in a direction A to deliver a sheet 11a. Simultaneously, rotation is transmitted to an idler roller 14 and a roll paper 11, which are rotated in directions B and C, respectively. The sheet 11a is unreeled from the roll paper 11, and is fed to the roller 15 after it passes the lower half periphery of the roller 14. In which case, since the roll paper 11 is rotated through the roller 14, high back tension is not applied on the sheet 11a, and there is no need to exert a high conveyance force on the sheet by means of the roller 15. Thus, the press force of a head spring 20 does not need a high force required for conveyance, and may be a force required only for recording. The curl of the sheet 11a is straightened during the passage of the sheet around the outer periphery of the roller 14.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a paper feeding device used in facsimile machines, copying machines, etc., and more particularly to a paper feeding device that feeds paper from a roll paper.

BACKGROUND OF THE INVENTION Conventionally, facsimile machines, single-frame copying machines, etc., which use roll paper as recording paper, have been widely used. When using roll paper, it is necessary to correct its curl, so
A roller or guide is provided in the path of the paper fed out from the roll paper to curve the paper in the direction opposite to the curl (for example, Utility Model Application No. 60-1750, Utility Model Application No. 606742). , JP-A-61-60554, JP-A-61124463, and JP-A-61-124464). However, in all of these devices, the means for correcting the curling is provided at a position away from the position where the roll paper is stored, and as a result, the overall size of the device is increased.

Therefore, as shown in Fig. 5, as a paper feeder equipped with a function to eliminate curling of roll paper while converting the device (KL), we installed a paper feeder that is close to the roll paper storage section 2 that stores roll paper 1 such as recording paper. Then, a curl removal plate 3 is provided, and a paper feed roller 4, a recording head 5, a recording head spring 6, etc. are provided near the curl removal plate 3, and the paper feed roller 4 removes the paper from the roll paper l to the paper 1a. There is known a structure in which the sheet la fed out from the roll paper I is bent by a curl removal plate 3 to remove the curl.

Problems to be Solved by the Invention However, with this configuration, there are problems in that uneven feeding occurs due to the paper feed roller and the effect of removing the paper texture varies.

The above problem arises for the following reasons. That is, when the paper is fed out by the paper feed roller, the rolled paper 1 is pulled and rotated by the fed out paper 1a, so back tension is generated in the paper according to the rotational load of the rolled paper, but the bank tension varies at the start of paper feeding, during paper feeding, and at the end of paper feeding, and also changes depending on the diameter of the roll paper, resulting in uneven feeding υ due to back tension fluctuations. Furthermore, the curl removal effect by the curl removing plate 3 differs depending on the magnitude of the bank tension, and as shown by the dotted line in FIG. 5, as the diameter of the roll paper becomes smaller, the bending angle by the curl removing plate 3 becomes smaller. Therefore, the habit removing effect becomes smaller.

The present invention has been made in view of the above-mentioned problems, and provides a paper feeding device that can prevent uneven feeding and stably remove curls regardless of the diameter of the roll paper. The purpose is to provide.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention aims to move a roll paper storage unit that stores roll paper in a direction toward and away from a paper feed roller that feeds paper from the roll paper. 1, the roll paper accommodated in the roll paper accommodating section and the paper feed roller are brought into contact with each other. A rotatable idler roller is provided, and the paper from the roll is guided by the outer periphery of the idler roller and sent to the paper feed roller.

Effect of the present invention With the above-described configuration, the roll paper is always pressed against the idler roller regardless of the diameter of the roll paper.
Since the paper is synchronously rotated by the paper feed roller via this idler roller, the back tension of the paper is extremely small and does not fluctuate. Because the paper always goes around the idler roller by half a turn and is sent to the paper feed roller,
It becomes possible to reduce curling.

Embodiment FIG. 1 is a perspective view showing a schematic configuration of a paper feeding device according to an embodiment of the present invention, and FIG. 2 is a schematic side view thereof. Figure 1,
In FIG. 2, 11 is a roll paper such as a recording paper, 11a is a paper pulled out from the roll paper 11, and 12 is a roll paper 1.
This is a roll paper accommodating section that rotatably accommodates 1. This roll paper storage section 12 is provided so as to be movable toward and away from a paper feed roller 15, which will be described later.
A force is applied in the direction of 5. 14 is a rotatable idler roller located between the roll paper 11 stored in the roll paper storage section I2 and the paper feed roll 15 and in contact with both; 15 is a paper feed roller that feeds the paper 11a in the sub-scanning direction;
16 is a paper feed motor that drives the paper feed roller 15 via a motor gear 17 and an idler gear 18; 19 is a paper 11a;
A recording head that records images, etc., on the recording head 19
This is a head spring that presses the paper 11a against the paper 11a.

Of these members, the idler roller 14, recording head 19, head spring, etc. are held in an opening/closing part 21 shown by dotted lines in FIG. 3, and by opening the opening/closing part upward, the paper feed roller 15 and It can be moved above the roll paper 11 accommodated in the roll paper storage section 12.

The operation of the paper feeding device configured as described above will be described below.

To cent the roll paper 11, as shown in Figure 3,
Open the opening/closing section 21 in which the idler roller 14 and recording head 19 are housed, and insert the roll paper 11 into the roll paper storage section 1.
2, pull out the paper 11a, place it on the paper feeder 5, and then close the opening/closing part 21. As a result, the idler roller 14 enters between the paper feed roller 15 and the roll paper 11 while pushing down a part of the paper 1, and as shown in FIGS.
As shown in the figure, due to the pressing force of the first spring 13, the paper feed roller 15, the idler roller 14, and the roller paper 11 come into close contact with each other, and the paper 11a from the roll paper 11 is fed through the lower half of the idler roller 14. It has reached the paper roller 15. This completes the paper setting.

Next, when feeding paper, the paper feed roller 15 is driven by the paper feed motor 16. For this purpose, paper feed roller 1
6 rotates in the direction shown by arrow A and feeds out the paper 11a.

At the same time, the rotation of the idler roller 14 and the roll paper 1
1, and both rotate in the directions of arrows B and C, respectively. In this manner, the paper 11a is unwound from the roll paper 1, passes through the lower half of the idler roller 14, reaches the paper feed roller 15, and is sent out. Here, as a result of the roll paper 11 being rotationally driven via the idler roller 14, a large back tension is not applied to the paper 11a pulled out by the paper feed roller 15, and therefore the paper feed roller 15 exerts a large conveyance force on the paper. There's no need to give. Therefore, the pressing force applied by the rad spring to recording does not need to be large enough to convey the paper as in the conventional example, but only the pressing force necessary for recording is sufficient.

Furthermore, while the paper 11a is unwound from the roll paper 11 and passes through the lower half of the idler roller 14, the curl of the paper 11a is corrected.

FIG. 4 is a schematic side view showing the state when the roll paper 11 is used and the remaining amount is less than υ. Even if the diameter of the roll paper is smaller than when the roll paper was started as shown in FIG. 2, the spring 13 is pushing the roll paper storage section 12, and the roll paper 11 and idler roller 14 are in close contact with each other with the paper sandwiched between them. are doing. Therefore, regardless of the winding diameter of the roll paper 11, the roll paper 11 is driven in the direction of arrow C, and the bank tension does not fluctuate, allowing stable paper feeding. Further, the paper 11a from the roll paper 11 is always transferred to the idler roller 14.
Since it passes through the lower half of the paper, the curl is corrected when passing through this part, and a sufficient curl removal effect can always be obtained.

Effects of the Invention As is clear from the above description, the present invention enables a roll paper storage unit that stores roll paper to move toward and away from a paper feed roller that feeds paper from the roll paper. Additionally, an idler is provided between the roll paper stored in the roll paper accommodating section and the paper feed roller and is rotatable in contact with the roll paper, which applies a force in the direction toward the paper feed slot roller by an elastic member. Since a roller is provided and the paper from the roll is guided by the outer periphery of the idler roller and sent to the paper feed roller, the roll paper is always pressed against the idler roller regardless of the diameter of the roll paper. The feed roller can be rotated synchronously with the feed roller via the idler roller, making it possible to feed the paper stably without uneven feeding.Moreover, the paper fed from the roll paper can always pass approximately half the way around the idler roller. This has the effect that it is possible to always reduce curling.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view of a paper feeding device according to an embodiment of the present invention, FIG. 2 is a schematic side view thereof, FIG. 3 is a schematic side view showing the opening/closing portion of the device in an open state, and FIG. 4 5 is a schematic side view showing a state in which the roll paper diameter is reduced in the above device, and FIG. 5 is a schematic side view of a conventional paper feeding device. 11... Roll paper, 12... Roll paper storage section, 13
...Elastic member, 14...Idler roller, 15...
-Paper feed roller, 16...Paper feed motor, 19...Recording head, addition...Head spring, 21...Opening/closing section. Name of agent: Patent attorney Shigetaka Awano and one other person

Claims (1)

[Claims] a paper feed roller that conveys the paper fed out from the roll paper; a roll paper storage section that stores the roll paper and is movable toward and away from the paper feed roller; an elastic member that applies a force in the direction; and an idler roller that is located between the roll paper stored in the roll paper storage section and the paper feed roller and that is rotatable in contact with both; A paper feeding device characterized in that the paper is guided by the outer periphery of the idler roller and sent to the paper feeding roller.