JPH0325389B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Background] In printers that use roll paper, it is required to remove slack when the roll paper is initially inserted in order to prevent the occurrence of paper jams. In many cases, the system relies on manual operation by a human operator, and poor operability is a problem. Furthermore, with ink jets, thermal printers, and the like that use special paper, there is a problem of deterioration of print quality due to sweat from human hands. Therefore, there is a need for the development of a roll paper slack winding mechanism that can easily eliminate the slack during the initial insertion of the roll paper without having to touch it by hand for a long time.

[Means for solving problems]

The present invention provides a roll paper slack winding mechanism for a printer in which roll paper is stored in a roll paper storage case that is movable between a mounting position and a non-mounting position with respect to a main body frame. A gear for transmitting rotational force to the roll paper is mounted on the directional end, and a rack gear that engages with the gear is provided in the main body frame, and the roll paper storage case is moved from a non-mounted position to a mounted position. The invention is characterized in that the roll paper is configured to rotate as the roll paper rotates.

[Effect]

The above technical means works as follows. When the roll paper storage case that stores the roll paper moves from the non-mounted position to the mounted position relative to the main body frame, that is, to the holding position where the roll paper is being printed,
A gear that engages with a rack gear rotates, and along with this rotation, the roll paper rotates and takes up slack in the winding.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 6. Figure 1 is a cross-sectional front view seen from the roll paper insertion direction, Figure 2 is a schematic diagram for explaining the operation when winding the roll paper, Figure 3 is a perspective view, and Figures 4 to 6 are the roll paper. FIG. 2 is a front view for explaining the operation during insertion and attachment.

First, the configuration will be explained. Reference numeral 1 denotes a substantially box-shaped frame made of synthetic resin. A hole 2 for ejecting recording paper is formed on the top surface of the frame 1, and a paper storage case 2, which will be described later, is provided on the side surface of the frame 1.
A hole 3 for putting in and taking out 0 is formed. 4
is a carriage, and the carriage 4 is capable of sliding along a main shaft 5 and a subshaft 6, both ends of which are fixed to the frame 1.
7 is a print head mounted on the carriage 4. 8 is a platen provided to face the printing head 7, and the platen 8 is connected to the frame 1.
Both ends thereof are fitted into a rotating shaft 9 which is rotatably supported. Reference numeral 10 denotes a paper bail roller provided so as to be in pressure contact with the platen 8, and the paper bail roller 10 is fitted onto a rotating shaft 11 rotatably supported by the frame 1 at both ends.
Reference numerals 12 and 13 denote paper guides fixed to the frame 1, one end of the gap formed between the paper guides 12 and 13 faces the print head 7 and the platen 8, and the other end faces the roll paper 30 described later. It is facing the , and is slightly wider. Reference numeral 14 denotes a guardrail, which is L-shaped when viewed from the length direction, and has a front stopper piece 15 and a rear stopper piece 16 formed near the end, and is fixed horizontally to the frame 1 with a pin 17. It has been done. 18 is a storage case feed roller;
is a rotating shaft 19 rotatably supported by the frame 1.
is fitted. Reference numeral 20 denotes a paper storage case made of synthetic resin, and is composed of a rectangular plate-shaped bottom surface 21 that contacts the storage case feeding roller 18 and a rectangular plate-shaped side surface 22 that is perpendicular to the bottom surface 21. The side surface 22 of the paper storage case 20 has the same shape as the hole 3 of the frame 1, and when the paper storage case 20 is completely inserted into the frame 1, it enters into the hole 3 and closes the hole 3. Reference numeral 23 denotes an L-shaped guardrail engaging piece formed on the bottom surface 21 of the paper storage case 20, which engages with the guardrail 14. That is, the bottom surface 21 of the paper storage case 20 moves on the storage case feeding roller 18 while being guided by the guardrail 14 . Furthermore, the movement range of the paper storage case 20 is restricted by the guide rail engaging pieces 23 abutting against the stopper pieces 15 and 16 provided on the four guide rails 14. A handle 24 is formed on the side surface 22 of the paper storage case 20 and is used to pull the paper storage case 20 when taking it out from the frame 1. 25 is a paper holding plate provided on the bottom surface 21 of the paper storage case 20. The paper holding plate 25 is L-shaped and fixed to the bottom surface 21 by pins 26. 27 has one end fixed to the paper holding plate 25 and the other end fixed to the paper retainer 28
This is a support post equipped with. Reference numeral 29 denotes a cylindrical core material in which a hole 29a into which the support column 27 is inserted is formed. 30 is a roll of paper wound around the outer periphery of the core material 29. Reference numeral 31 denotes a roll paper pressing plate in the form of a donut-shaped disc, which is rotatably mounted around the pillar 27. 32 is a tube 32a
The gear is integrally formed with a donut-shaped disk 32b having teeth on the outer periphery, and is rotatably mounted around the support column 27. Reference numeral 33 denotes a tension spring mounted around the support 27, which presses the gear 32 against the roll paper press plate 31 and presses the roll paper press plate 31 against the roll paper 30. 34 is a rack gear having teeth on its upper surface for rotating the gear 32, and is fixed to the frame 1 horizontally by a mounting piece 35 at a height such that it engages with the lower end of the gear 32. There is. The configuration has been described above; the guide rail 14, the storage case feeding roller 18, the guide rail engaging piece 23, the paper holding plate 2
5. Support column 27, roll paper pressing plate 31, gear 3
2. It is assumed that there are two pairs of tension springs 33 and one pair of rack gears 34, each at symmetrical positions with the roll paper 30 in between.

Next, the effect will be explained.

First, the paper storage case 20 and the guide rail engagement piece 2
3 until it hits the front stopper piece 15.

Next, as shown in FIG. 2, in order to insert the roll paper 30 between the two roll paper press plates 31 in such a direction that the roll paper 30 is wound to the left when the platen 8 is viewed to the right, first As shown in FIG. 4, one of the support columns 27 is inserted into the hole 29a, and the roll paper 30 is pushed down in the direction of arrow a, against the elastic force of the tension spring 33, until it becomes horizontal as shown in FIG. Then, by moving the roll paper 30 in the direction of arrow b in FIG. 5 while keeping it in a horizontal state and inserting the other support 27 into the hole 29a and releasing the hand, the elastic forces of the left and right tension springs 33 are equal, so the sixth
As shown in the figure, the roll paper 30 is inserted between two roll paper pressing plates 31 with both supports 27 inserted into the holes 29a by the same length.

Next, pull out a large amount of roll paper 30, hold the tip of the roll paper 30, pass it through the gap between paper guides 12 and 13, and then pass it between the print head 7 and platen 8 between platen 8 and paper bail roller 1.
Insert between 0. In particular, by manually turning the knob 36 shown in FIG. 3, the platen 8 and the paper bail roller 10 are rotated, and the roll paper 3
0 to the discharge hole 2.

Finally, when the paper storage case 20 is pushed in until the guide rail engagement piece 23 hits the rear stopper piece 16, the gear 32 engages with the rack gear 34, and the gear 32 continues to rotate in the direction of arrow A shown in FIG. move. The roll paper presser plate 31 and the gear 32 are pressed against each other by the appropriate pressure of the tension spring 33, and when there is slack in the paper, the rotation of the gear 32 is transmitted to the roll paper presser plate 31 by frictional force. The frictional force between the roll paper pressing plate 31 and the roll paper 30 is also transmitted to the roll paper 30, and the roll paper 30 rotates in the direction of arrow B in FIG. 2 to take up the slack paper. If the winding of the slack paper is completed before the paper storage case 20 is completely pushed into the frame 1, and a considerable amount of tension is applied to the roll paper, slippage may occur between the roll paper holding plate 31 and the gear 32. Since the rotation of the gear 32 is not transmitted to the roll paper pressing plate 31, the roll paper 30 does not rotate. Therefore, as described above, even if the paper sag is eliminated midway through, the roll paper 30 will not be torn. Note that the frictional force between the roll paper 30 and the roll paper presser plate 31 is greater than the frictional force between the roll paper presser plate 31 and the gear 32. By the above-described actions, the insertion of the roll paper 30 is completed without any paper sagging.

For reference, the formula for calculating the length of slack paper that can be wound by this mechanism at the time of initial insertion, that is, the length of slack paper when inserted into the pulled out paper storage case 20, is shown below. = (diameter of roll paper 30) x (periphery) x (number of teeth of rack gear 39 that meshes with gear 32) ÷ (gear 3
2) - (movement distance of the paper storage case 20). Assuming that the roll paper 30 has a diameter of 8 cm, the rack gear 34 has 27 teeth, the gear 32 has 18 teeth,
When the moving distance of the paper storage case 20 is 20 cm, =8 x 3.14 x 27/18-20≒18 (cm), and it is possible to wind up loose paper up to 18 cm. Note that by changing the number of teeth, etc., the length of the paper slack that can be rolled up can be adjusted.

〔Effect of the invention〕

As explained above, according to the present invention, the roll paper insert comprises a gear attached to the axial end of the roll paper for transmitting rotational force to the roll paper, and a rack gear for engaging with the gear. Since the mounting mechanism is mounted on the machine, the slack during the initial insertion of the roll paper can be eliminated by simply pushing the paper storage case with the roll paper inserted into the frame. (1) There is no need to wind up the slack paper. This simplifies the work of inserting roll paper.

(2) Since it automatically winds up loose paper, there is no need to touch the paper for a long time, and there is no sweat from your hands on the paper, resulting in high print quality.

It has remarkable effects such as

[Brief explanation of drawings]

Figures 1 to 6 all show one embodiment of the present invention, with Figure 1 being a cross-sectional front view seen from the roll paper insertion direction, and Figure 2 being a schematic diagram for explaining the operation when winding up the roll paper. Figure 3 is a perspective view, Figures 4 to 6
The figure is a front view for explaining the operation when inserting roll paper. 30...roll paper, 32...gear, 34...rack gear.

Claims (1)

[Scope of Claims] 1. In a roll paper slack winding mechanism in a printer in which roll paper is stored in a roll paper storage case movable between a mounting position and a non-mounting position with respect to a main body frame, the roll paper slack winding mechanism A gear for transmitting rotational force to the roll paper is attached to the axial end of the paper, and a rack gear that engages with the gear is provided in the main body frame, and the roll paper storage case is moved from the non-installation position to the installation position. 1. A slack winding mechanism for roll paper in a printer, characterized in that the roll paper is configured to rotate as the roll paper moves. 2. The roll paper slack winding mechanism in a printer according to claim 1, wherein the rotational force is transmitted by a frictional force between the roll paper and the gear. ”